bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of the incorporation of saturated fatty acids on the mechanical and barrier properties of biodegradable films
Authors: Nobrega Marcelo Medre , Olivato Juliana Bonametti , Grossmann Maria Victoria Eiras , Bona Evandro , Yamashita Fabio
Published: November 2011

The effects of saturated fatty acids at a concentration of 1.5% on the mechanical and barrier properties of starch‐based films were evaluated in films prepared with two concentrations of glycerol, 20 and 25%. The water vapor permeability (WVP) was determined at three ranges of relative humidity, RH, (0–33, 33–64 and 64–97%). In all cases, an increase in WVP values was observed with increasing RH. SEM images showed a more homogeneous and compact structure in the films with caproic and lauric acids. The films with fatty acids showed higher elongation and maximum stress, and they had Young's modulus values close to those of the control; thus, the addition of fatty acids did not impair the mechanical properties. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Random copolymers based on trimethylene carbonate and ε‐caprolactone for implant applications: Synthesis and properties
Authors: Yang Li‐Qun , Yang Dan , Guan Yan‐Min , Li Jian‐Xin , Li Miao
Published: November 2011

Random copolymers of trimethylene carbonate (TMC) and ε‐caprolactone (CL) have been synthesized by ring‐opening polymerization of TMC and CL in the presence of stannous octoate. The effects of feeding dose, reaction temperature and polymerization time, and effect of catalyst content on the copolymerization were investigated. The results showed that the composition of the copolymers was in good agreement with the feeding dose, and the molecular weight of the copolymers decreased firstly with increasing CL content and then increased. The decrease in the reaction temperature, polymerization time and catalyst content would increase the molecular weight of the copolymers. Furthermore, the feeding dose affected the thermal and mechanical properties of the copolymer largely, and the possessing different properties of random copolymers could be obtained by adjusting the copolymer compositions. This work could optimize the polymerization conditions to achieve the copolymers with controlled properties for implant applications. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
In Situ synthesis of multiblock copolymers of poly(ϵ‐caprolactone) with different poly(ether diols) based polyurethane by reactive extrusion
Authors: Weng Shengguang , Xia Zhean , Chen Jianding , Gong Luanluan , Xu Ruijun
Published: November 2011

Polyurethanes with multiblock copolymers of poly(ϵ‐caprolactone) (PCL) and poly(tetramethylene oxide) glycol (PTMG) or poly(ethylene glycol) (PEG) as a soft segment were synthesized in situ via reactive extrusion from ϵ‐caprolactone (CL) and 4,4′‐diphenylmethane diisocyanate (MDI). The titanium alkoxide mixture generated from an ester‐exchange reaction between titanium propoxide [Ti(OPr)4], and excessive PTMG or PEG was used as an initiator and catalyst. Compared to the reported fabrication of polycaprolactone‐based polyurethane (PCLU), the in situ reactive extrusion preparation not only explored a new rapid route for the fabrication of PCLU but also offered a simplified, controllable approach for the production of PCLU in a successive mass scale. A series of PTMG–PCLUs and PEG–PCLUs with different PCL block‐average degrees of polymerization (DPn's) were prepared by only an adjustment of the relative concentration of CL in the reaction system, with a certain constant molar ratio of MDI to titanium alkoxide. 1H‐NMR, gel permeation chromatography, and differential scanning calorimetry results indicate that all of the CL monomers were converted in the polymerization, and the molecular weight of the copolymers was about 8 × 104 g/mol with a polydispersity index of approximate 2.4. With an increase in the PCL block‐average DPn in PTMG–PCLU from 25 to 40, the tensile strength increased from 16.5 to 22.7 MPa, and the melting point increased from 46.1 to 49.5°C. It was also verified by PEG–PCLU prepared with organic Ti of lowered content in the initiator mixture that the mechanical properties could be greatly affected and dropped with decreasing content of organic Ti in the initiator mixture. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Biopolymers as effective fillers in natural rubber: Composites versus biocomposites
Authors: Valodkar Mayur , Thakore Sonal Ishit
Published: November 2011

Biocomposites of natural rubber (NR) blends were prepared with a variety of fillers obtained from renewable resources by a mastication technique. They were characterized for their mechanical properties and morphologies and compared with composites of the conventional filler carbon black (c‐black). The biopolymers exhibited an interesting trend and imparted strength to NR that was quite comparable to c‐black. Up to 30 phr of the fillers could be successfully incorporated; this led to enhancements in the mechanical strength. The properties were found to vary with the type and ratio of filler, namely, starch, cellulose, and chitin. The optimum mechanical strength of the biocomposites was observed at 10 phr. The results were interpreted on the basis of the morphology by scanning electron microscopy, which revealed strong filler–polymer interactions. The moisture‐uptake characteristics of the composites were studied. It was found that addition of biofillers did not lead to a significant increase in the moisture absorption. Furthermore, as the adhesion between the polymer matrix and fillers increased, the water uptake decreased. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
HPLC‐MS/MS method to determine genipin in rat plasma after hydrolysis with sulfatase and its application to a pharmacokinetic study
Authors: Ding Yue , Zhang Tong , Tao Jian‐Sheng , Tan Bo , Guo Chun‐Rong , Yang Li
Published: November 2011

A sensitive high‐performance liquid chromatography–tandem mass spectrometry (LC‐MS/MS) method was developed for the quantification of genipin in rat plasma after hydrolysis with sulfatase. Genipin could not be detected directly as it could be transformed into other forms such as conjugated‐genipin immediately after administration. The conjugated genipin could be hydrolyzed by sulfatase to genipin. The conditions of hydrolysis were investigated. Genipin and the internal standard, peoniflorin (IS), were separated on a reversed‐phase column by gradient elution and detected using an electrospray ion source on a 4000 QTrap triple‐quadrupole mass spectrometer. The quantification was performed using multiple reaction monitoring with selected precursor‐product ion pairs of the transitions m/z 225.0 → 122.7 and m/z 479.1 → 449.1 for genipin and peoniflorin. The assay was linear over the concentration range of 1.368–1368 ng/mL, with correlation coefficients of 0.9989. Intra‐ and inter‐day precisions and accuracy were all within 15%. The lower limit of quantification was 1.368 ng/mL. The recoveries of genipin and peoniflorin were more than 53.3 and 51.2%. The highly sensitive method was successfully applied to estimated pharmacokinetic parameters of genipin following oral and intravenous administration to rats. The absolute bioavailability of genipin was 80.2% in rat, which is the first report. Copyright © 2011 John Wiley & Sons, Ltd.
The Mechanism of Low‐Temperature CO Oxidation on IB Group Metals and Metal Oxides
Authors: Wei Zi‐Zhang , Li Dui‐Chun , Pang Xian‐Yong , Lv Cun‐Qin , Wang Gui‐Chang
Published: November 2011

CO oxidation on the IB group metals [Cu(111), Ag(111), and Au(111)] and corresponding metal oxides [Cu2O(100), Ag2O(100), and Au2O(100)] has been studied by means of density functional theory calculations with the aim to shed light on the reaction mechanism and catalytic activity of metals and metal oxides. The calculated results show that 1) the molecular oxygen mechanism is favored on Ag(111) and Au(111), but the atomic oxygen mechanism is favored on Cu(111); 2) the metal‐terminated metal oxide shows very low activity for CO oxidation; 3) the lattice oxygen can react either with gas phase CO or the absorbed CO molecule on oxygen‐terminated metal oxides; and 4) the reaction barrier for CO oxidation follows the order of M2O(100)–O<M(111)<M2O(100)–M (M=Cu, Ag, Au); namely the M2O(100)–O shows higher activity than does the corresponding metal. By analyzing the factor that controls the energy barrier, it was found that the interaction energy between two CO molecules and one O atom at the transition state plays an important role in determining the trend in the barrier.
In vivo time‐lapse imaging of cell proliferation and differentiation in the optic tectum of Xenopus laevis tadpoles
Authors: Bestman Jennifer E. , Lee‐Osbourne Jane , Cline Hollis T.
Published: November 2011

We analyzed the function of neural progenitors in the developing central nervous system of Xenopus laevis tadpoles by using in vivo time‐lapse confocal microscopy to collect images through the tectum at intervals of 2–24 hours over 3 days. Neural progenitor cells were labeled with fluorescent protein reporters based on expression of endogenous Sox2 transcription factor. With this construct, we identified Sox2‐expressing cells as radial glia and as a component of the progenitor pool of cells in the developing tectum that gives rise to neurons and other radial glia. Lineage analysis of individual radial glia and their progeny demonstrated that less than 10% of radial glia undergo symmetric divisions resulting in two radial glia, whereas the majority of radial glia divide asymmetrically to generate neurons and radial glia. Time‐lapse imaging revealed the direct differentiation of radial glia into neurons. Although radial glia may guide axons as they navigate to the superficial tectum, we find no evidence that radial glia function as a scaffold for neuronal migration at early stages of tectal development. Over 3 days, the number of labeled cells increased 20%, as the fraction of radial glia dropped and the proportion of neuronal progeny increased to approximately 60% of the labeled cells. Tadpoles provided with short‐term visual enhancement generated significantly more neurons, with a corresponding decrease in cell proliferation. Together these results demonstrate that radial glial cells are neural progenitors in the developing optic tectum and reveal that visual experience increases the proportion of neurons generated in an intact animal. J. Comp. Neurol. 520:401–433, 2012. © 2011 Wiley Periodicals, Inc.
Canakinumab for the treatment of adult and pediatric cryopyrin‐associated periodic syndromes (CAPS)
Authors: Patel Aarat M. , Torok Kathryn S.
Published: November 2011

The cryopyrin‐associated periodic syndromes (CAPS) comprise three rare autoinflammatory disorders: familial cold autoinflammatory syndrome, Muckle–Wells syndrome, and neonatal‐onset multisystem inflammatory disorder. A mutation in the NLRP3 (CIAS1) gene, encoding cryopyrin, leads to inflammation and results in fever, chills, urticarial rash, arthralgias, conjunctivitis, and other difficult‐to‐control systemic features. Major advances in understanding interleukin‐1 (IL‐1) have led to better treatment options. This review focuses on a promising new medication, canakinumab, which is a recombinant, human anti‐human‐IL‐1β monoclonal antibody that has been effective in treating adult and pediatric CAPS. Drug Dev Res 72:553–560, 2011. © 2011 Wiley Periodicals, Inc.
T‐cell targeted therapies in autoimmune diseases
Authors: Alnaimat Fatima , Sidhu Paramvir , Sarkar Sujata
Published: November 2011

Significant advances have been made during the past decade in the understanding of autoimmune diseases and in the development of therapeutics targeting various immune pathways. T‐cell‐mediated immune dysregulation occurs in a variety of autoimmune conditions, including rheumatoid arthritis, inflammatory bowel disease, and multiple sclerosis. Inhibition of the T‐cell function using CTLA‐4Ig is currently approved for management of rheumatoid arthritis. Select therapies targeting adhesion molecules are used for the management of patients with psoriasis and multiple sclerosis. Therapeutics targeting tumor necrosis factor‐α (TNF‐α), a cytokine secreted by T cells, is widely used in patients with rheumatoid arthritis and inflammatory bowel disease. Furthermore, several therapies target a variety of molecules related to T cells that are under development or undergoing clinical trials. Drug Dev Res 72:585–597, 2011. © 2011 Wiley Periodicals, Inc.
Certolizumab pegol therapy of rheumatoid arthritis: Overview
Authors: Zidi Ines , Mnif Wissem , Bouaziz Aicha , Amor Nidhal Ben
Published: November 2011

First‐line treatment for moderate to severe rheumatoid arthritis (RA) has been the use of disease‐modifying anti‐rheumatic drugs (DMARDs), e.g., methotrexate. Because of the cases of failure reported to respond to available treatments, newer RA drugs including tumor necrosis factor (TNF‐α) blockers have emerged. Certolizumab pegol (CZP) is a unique polyethylene glycolated (PEG) humanized monoclonal antibody designed specifically to target TNF‐α pro‐inflammatory cytokine. Given that its properties closely reflect its PEG fragment, CZP has demonstrated a clear efficiency. Pharmacokinetics and pharmacodynamics of CZP are described together with Phase II and III CZP clinical studies focused on CZP efficiency and safety. We also discuss the future of CZP and new clinical studies that might help physicians in their choice of CZP among available TNF‐α blockers. Drug Dev Res 72:603–614, 2011. © 2011 Wiley Periodicals, Inc.
Segregated and overlapping neural circuits exist for the production of static and dynamic precision grip force
Authors: Neely Kristina A. , Coombes Stephen A. , Planetta Peggy J. , Vaillancourt David E.
Published: November 2011

A central topic in sensorimotor neuroscience is the static‐dynamic dichotomy that exists throughout the nervous system. Previous work examining motor unit synchronization reports that the activation strategy and timing of motor units differ for static and dynamic tasks. However, it remains unclear whether segregated or overlapping blood‐oxygen‐level‐dependent (BOLD) activity exists in the brain for static and dynamic motor control. This study compared the neural circuits associated with the production of static force to those associated with the production of dynamic force pulses. To that end, healthy young adults (n = 17) completed static and dynamic precision grip force tasks during functional magnetic resonance imaging (fMRI). Both tasks activated core regions within the visuomotor network, including primary and sensory motor cortices, premotor cortices, multiple visual areas, putamen, and cerebellum. Static force was associated with unique activity in a right‐lateralized cortical network including inferior parietal lobe, ventral premotor cortex, and dorsolateral prefrontal cortex. In contrast, dynamic force was associated with unique activity in left‐lateralized and midline cortical regions, including supplementary motor area, superior parietal lobe, fusiform gyrus, and visual area V3. These findings provide the first neuroimaging evidence supporting a lateralized pattern of brain activity for the production of static and dynamic precision grip force. Hum Brain Mapp, 2013. © 2011 Wiley Periodicals, Inc.
Differential neural activity in the recognition of old versus new events: An Activation Likelihood Estimation Meta‐Analysis
Authors: Kim Hongkeun
Published: November 2011

This study presents a meta‐analysis comparing hit and correct rejection (CR) conditions across 48 fMRI studies. Old/new (hit > CR) effects associated most consistently with (1) components of the default‐mode network, including the left angular gyrus, bilateral precuneus, and bilateral posterior cingulate regions, which may support the mental re‐experiencing of an old event, or ecphory; (2) components of the cognitive‐control network, involving the left dorsolateral and dorsomedial prefrontal cortex and bilateral intraparietal sulcus regions, which may mediate memory and non‐memory control functions; and (3) the caudate nucleus, a key part of the brain's reward system that may support the satisfaction tied to target‐detection. Direct comparisons of old/new effects between item versus source retrieval and “remember” versus “know” retrieval yielded three main sets of findings. First, default‐mode network regions showed greater old/new effects in conditions associated with richer ecphoric processing. Second, cognitive‐control network regions showed greater old/new effects in conditions associated with a greater demand for strategic‐retrieval processing. Third, the caudate nucleus showed greater old/new effects in conditions tied to greater confidence in target‐detection. New/old (CR > hit) effects most strongly associated with the bilateral medial temporal lobe, possibly reflecting greater encoding‐related activity for new than for old items, and the right posterior middle temporal regions, possibly reflecting repetition‐related neural priming for old items. In conclusion, neural activity distinguishing old from new events comprises an ensemble of multiple memory‐specific activities, including encoding, retrieval, and priming, as well as multiple types of more general cognitive activities, including default‐mode, cognitive‐control, and reward processing. Hum Brain Mapp, 2013. © 2011 Wiley Periodicals, Inc.
Cortical oscillatory changes in human middle temporal cortex underlying smooth pursuit eye movements
Authors: Dunkley Benjamin T. , Freeman Tom C.A. , Muthukumaraswamy Suresh D. , Singh Krish D.
Published: November 2011

Extra‐striate regions are thought to receive non‐retinal signals from the pursuit system to maintain perceptual stability during eye movements. Here, we used magnetoencephalography (MEG) to study changes in oscillatory power related to smooth pursuit in extra‐striate visual areas under three conditions: ‘pursuit’ of a small target, ‘retinal motion’ of a large background and ‘pursuit + retinal motion’ combined. All stimuli moved sinusoidally. MEG source reconstruction was performed using synthetic aperture magnetometry. Broadband alpha–beta suppression (5–25 Hz) was observed over bilateral extra‐striate cortex (consistent with middle temporal cortex (MT+)) during all conditions. A functional magnetic resonance imaging study using the same experimental protocols confirmed an MT+ localisation of this extra‐striate response. The alpha–beta envelope power in the ‘pursuit’ condition showed a hemifield‐dependent eye‐position signal, such that the global minimum in the alpha–beta suppression recorded in extra‐striate cortex was greatest when the eyes were at maximum contralateral eccentricity. The ‘retinal motion’ condition produced sustained alpha–beta power decreases for the duration of stimulus motion, while the ‘pursuit + retinal motion’ condition revealed a double‐dip ‘W’ shaped alpha–beta envelope profile with the peak suppression contiguous with eye position when at opposing maximum eccentricity. These results suggest that MT+ receives retinal as well as extra‐retinal signals from the pursuit system as part of the process that enables the visual system to compensate for retinal motion during eye movement. We speculate that the suppression of the alpha–beta rhythm reflects either the integration of an eye position‐dependent signal or one that lags the peak velocity of the sinusoidally moving target. Hum Brain Mapp, 2013. © 2011 Wiley Periodicals, Inc.
Whole‐brain white matter disruption in semantic and nonfluent variants of primary progressive aphasia
Authors: Schwindt Graeme C. , Graham Naida L. , Rochon Elizabeth , Tang‐Wai David F. , Lobaugh Nancy J. , Chow Tiffany W. , Black Sandra E.
Published: November 2011

Semantic (svPPA) and nonfluent (nfPPA) variants of primary progressive aphasia are associated with distinct patterns of cortical atrophy and underlying pathology. Little is known, however, about their contrasting spread of white matter disruption and how this relates to grey matter (GM) loss. We undertook a structural MRI study to investigate this relationship. We used diffusion tensor imaging, tract‐based spatial statistics, and voxel‐based morphometry to examine fractional anisotropy (FA) and directional diffusivities in nine patients with svPPA and nine patients with nfPPA, and compared them to 16 matched controls after accounting for global GM atrophy. Significant differences in topography of white matter changes were found, with more ventral involvement in svPPA patients and more widespread frontal involvement in nfPPA individuals. However, each group had both ventral and dorsal tract changes, and both showed spread of diffusion abnormalities beyond sites of local atrophy. There was a clear dissociation in sensitivity of diffusion tensor imaging measures between groups. SvPPA patients showed widespread changes in FA and radial diffusivity, whereas changes in axial diffusivity were more restricted and proximal to sites of GM atrophy. NfPPA patients showed isolated changes in FA, but widespread axial and radial diffusivity changes. These findings reveal the extent of white matter disruption in these variants of PPA after accounting for GM loss. Further, they suggest that differences in the relative sensitivity of diffusion metrics may reflect differences in the nature of underlying white matter pathology in these two subtypes. Hum Brain Mapp, 2013. © 2011 Wiley Periodicals, Inc.
Surgical management of squamous cell carcinoma of the soft palate: Factors predictive of outcome
Authors: Iyer N. Gopalakrishna , Nixon Iain J. , Palmer Frank , Kim Leslie , Whitcher Monica , Katabi Nora , Ghossein Ronald , Shah Jatin P. , Patel Snehal G. , Ganly Ian
Published: November 2011

Background

Squamous cell carcinoma of the soft palate (SCCSP) is uncommon. The aim of this study was to report our experience and identify factors predictive of outcome.

Methods

Between 1976 and 2005, 186 patients with SCCSP were treated with curative intent. In all, 150 patients had primary surgery, of whom 112 patients (75%) had cT1/T2 tumors and 103 patients (69%) had cN0 necks. Overall survival (OS), disease‐specific survival (DSS), and recurrence‐free survival (RFS) were determined by the Kaplan–Meier method and factors predictive of outcome were identified.

Results

Five‐year OS, DSS, and RFS for surgical patients were, respectively, 52%, 71%, and 56%. DSS for cT1T2N0 and cT1T2N+ were 79% and 56%, respectively. For OS and DSS, multivariate analysis showed cN classification was predictive of outcome. For RFS and distant RFS, margin status was a significant predictor, whereas the cT classification was a significant predictor for local RFS.

Conclusions

Outcomes of patients with early‐stage SCCSP managed by surgery were excellent. These patients may be suitable for transoral robotic or endoscopic surgical procedures. © 2011 Wiley Periodicals, Inc. Head Neck, 2011
Unlocking the value of Web 2.0 technologies for training and development: The shift from instructor‐controlled, adaptive learning to learner‐driven, generative learning
Authors: London Manuel , Hall MJ
Published: November 2011

Traditional instruction is adaptive—that is, instructor‐driven, face‐to‐face and/or online training to teach skills and knowledge and convey information, policies, and procedures. In contrast, generative learning is learner‐driven, collaborative, and problem‐focused. Web 2.0 technologies can support both types of learning but are especially valuable for generative learning. This article reviews learning processes and Web 2.0 capabilities, describes two case examples, outlines ways to design Web 2.0 training applications, and discusses the changing role of learning professionals from delivering structured, one‐way adaptive learning to designing and facilitating generative learning opportunities. The article concludes with ideas for corporate education and research on Web 2.0–based learning processes, including utilizing the technology to track and improve learning. © 2011 Wiley Periodicals, Inc.
Matrix metalloproteinase‐9 in homocysteine‐induced intestinal microvascular endothelial paracellular and transcellular permeability
Authors: Munjal Charu , Tyagi Neetu , Lominadze David , Tyagi Suresh C.
Published: November 2011

Although elevated levels of homocysteine (Hcy), known as hyperhomocysteinemia (HHcy), is associated with inflammatory bowel disease (IBD), the mechanism of Hcy action is unclear. In the present study, we tested the hypothesis that HHcy activates matrix metalloproteinase‐9 (MMP‐9), which in turn enhances permeability of human intestinal microvascular endothelial cell (HIMEC) layer by decreasing expression of endothelial junction proteins and increasing caveolae formation. HIMECs were grown in Transwells and treated with 500 µM Hcy in the presence or absence of MMP‐9 activity inhibitor. Hcy‐induced permeability to FITC‐conjugated bovine serum albumin (FITC‐BSA) was assessed by measuring fluorescence intensity of solutes in the Transwells' lower chambers. The cell–cell interaction and cell barrier function was estimated by measuring trans‐endothelial electrical impedance. Confocal microscopy and flow cytometry were used to study cell junction protein expressions. Hcy‐induced changes in transcellular transport of HIMECs were estimated by observing formation of functional caveolae defined as caveolae labeled by cholera toxin and antibody against caveolin‐1 and one that have taken up FITC‐BSA. Hcy instigated HIMEC monolayer permeability through activation of MMP‐9. The increased paracellular permeability was associated with degradation of vascular endothelial cadherin and zona occludin‐1 and transcellular permeability through increased caveolae formation in HIMECs. Elevation of Hcy content increases permeability of HIMEC layer affecting both paracellular and transcellular transport pathways, and this increased permeability was alleviated by inhibition of MMP‐9 activity. These findings contribute to clarification of mechanisms of IBD development. J. Cell. Biochem. 113: 1159–1169, 2012. © 2011 Wiley Periodicals, Inc.
A new approximate method for the stochastic simulation of chemical systems: The representative reaction approach
Authors: Kadam Shantanu , Vanka Kumar
Published: November 2011

We have developed two new approximate methods for stochastically simulating chemical systems. The methods are based on the idea of representing all the reactions in the chemical system by a single reaction, i.e., by the “representative reaction approach” (RRA). Discussed in the article are the concepts underlying the new methods along with flowchart with all the steps required for their implementation. It is shown that the two RRA methods {with the reaction
$ 2A \rightarrow B $
as the representative reaction (RR)} perform creditably with regard to accuracy and computational efficiency, in comparison to the exact stochastic simulation algorithm (SSA) developed by Gillespie and are able to successfully reproduce at least the first two moments of the probability distribution of each species in the systems studied. As such, the RRA methods represent a promising new approach for stochastically simulating chemical systems. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2012
QM/MM refinement and analysis of protein bound retinoic acid
Authors: Li Xue , Fu Zheng , Merz Kenneth M.
Published: November 2011

Retinoic acid (RA) is a vitamin A derivative, which modifies the appearance of fine wrinkles and roughness of facial skin and treats acne and activates gene transcription by binding to heterodimers of the retinoic acid receptor (RAR) and the retinoic X receptor (RXR). There are series of protein bound RA complexes available in the protein databank (PDB), which provides a broad range of information about the different bioactive conformations of RA. To gain further insights into the observed bioactive RA conformations we applied quantum mechanic (QM)/molecular mechanic (MM) approaches to re‐refine the available RA protein‐ligand complexes. MP2 complete basis set (CBS) extrapolations single energy calculations are also carried out for both the experimental conformations and QM optimized geometries of RA in the gas as well as solution phase. The results demonstrate that the re‐refined structures show better geometries for RA than seen in the originally deposited PDB structures through the use of QMs for the ligand in the X‐ray refinement procedure. QM/MM re‐refined conformations also reduced the computed strain energies found in the deposited crystal conformations for RA. Finally, the dependence of ligand strain on resolution is analyzed. It is shown that ligand strain is not converged in our calculations and is likely an artifact of the typical resolutions employed to study protein‐ligand complexes. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2012
Regulatory role of zinc during aluminium‐induced altered carbohydrate metabolism in rat brain
Authors: Singla Neha , Dhawan D.K.
Published: November 2011

Aluminium is considered an environmental neurotoxicant and causes many neurological disorders, whereas zinc is vital for many biological functions. The present study was carried out to investigate the role of Zn, if any, in mitigating the adverse effects inflicted by Al on carbohydrate metabolism in rat brain. Male Sprague‐Dawley rats weighing 140–160 g were divided into four different groups: normal control, Al‐treated (100 mg/kg b.w./day in drinking water via oral gavage), Zn‐treated (227mg/liter in drinking water), and combined Al‐ and Zn‐treated rats. All the treatments were continued for 2 months, and their effects on carbohydrate‐metabolizing enzymes were studied. Additionally, expressions of the proteins glycogen synthase kinase‐3 (GSK3) and protein phosphatase (PP1), which help in regulating carbohydrate energy metabolism, were also studied. Al treatment resulted in increased activities of the glucose‐6‐phosphatase (G6P), glucose‐6‐isomerase (G6I), and lactate dehydrogenase (LDH), whereas the activities of hexokinase and succinate dehydrogenase (SDH) and glycogen content were decreased. Moreover, no significant change was observed in the biochemical parameters upon Zn supplementation alone. However, Zn supplementation to Al‐treated rats was able to reduce significantly the Al‐induced increased activities of G6P, G6I, and LDH, but it elevated the levels of hexokinase, SDH, and glycogen. Furthermore, Al treatment increased the protein expression of GSK3 and decreased the PP1 expression, which were found to be reversed upon Zn administration. Hence, Zn is effective in regulating theAl‐induced alterations in carbohydrate metabolism. © 2011 Wiley Periodicals, Inc.
Expression of sorting nexin 12 is regulated in developing cerebral cortical neurons
Authors: Mizutani Reiko , Nakamura Kazuaki , Kato Natsuko , Aizawa Kazuko , Miyamoto Yuki , Torii Tomohiro , Yamauchi Junji , Tanoue Akito
Published: November 2011

The sorting nexins (SNXs) are a family of proteins functioning in diverse processes, including endocytosis, endosomal sorting, and endosomal signaling. Sorting nexin 12 (SNX12) is one of the SNXs family members; however, its function remains unknown. To clarify the function of SNX12, in this study, we first investigated the expression profiles in mice, particularly in the central nervous system (CNS), and then analyzed the functional role on neurite outgrowth. We found that SNX12 was widely expressed in the adult mouse CNS and that its expression level was higher in the cerebral cortex than in other examined regions. SNX12 expression was detected in the neurons but not the glial cells of the adult mouse cerebral cortex. In the fetal brain, SNX12 expression increased during the embryonic stage and gradually decreased after birth. Although the immunoreactivities of SNX12 were widespread in the cerebral cortical cells in the fetal brain, the immunopositive signals of SNX12 were more intense in the postmitotic neurons in the cortical plate than in the proliferating precursor cells in the ventricular zone, suggesting that SNX12 plays critical roles in the postmitotic neurons during cerebral cortical development. Furthermore, in mouse neuroblastoma and N1E‐115 cells and rat primary cortical neurons, SNX12 expression was increased as neurite outgrowth progressed and the knockdown of SNX12 attenuated the outgrowth of neurites. These results suggest that SNX12 regulates neurite formation during cerebral cortical development. © 2011 Wiley Periodicals, Inc.
Self‐injury in incarcerated juvenile females: Contributions of mental health and traumatic experiences
Authors: McReynolds Larkin S. , Wasserman Gail A.
Published: November 2011

Despite evidence supporting a connection between child maltreatment and self‐injury, there is disagreement regarding a particular connection to sexual abuse because types of trauma exposure often co‐occur. To examine these associations efficiently, we considered a sample of incarcerated juvenile females, where rates of both trauma exposure and self‐injury would be expected to be elevated. Adolescent females (N = 220) reported on history of self‐injurious behavior on the Voiced Index of Self‐injurious Actions, as well as psychiatric disorder. A common set of features was associated with cutting and with self‐injury in general. Both were more likely in those initiating delinquent activities when younger and in those currently meeting criteria for major depressive disorder, or with a previous suicide attempt. Adjusting for those features, report of self‐injury was approximately doubled among those disclosing prior traumatic exposure that was sexual, OR = 2.66, 95% CI [1.38, 5.15], or nonsexual, OR = 2.18, 95% CI [1.17, 4.04]. Exposure to early traumatic events, such as child maltreatment, likely contributes to a set of adverse experiences, including delinquent activity, mood disorder, and self‐injury. Findings contribute to work demonstrating the importance of dissociation both as a consequence of victimization and as a key feature underlying self‐injurious behavior.
Time‐of‐flight mass spectrometry for time‐resolved measurements: Some developments and applications
Authors: Baeza‐Romero Maria Teresa , Blitz Mark A. , Goddard Andrew , Seakins Paul W.
Published: November 2011

In this paper, the time resolution for kinetic studies of reactions with mass spectrometric detection is characterized in detail, and it is shown how this allows faster kinetic processes to be determined. The time‐resolved technique used pulsed laser photolysis to initiate reaction and a time‐of‐flight mass spectrometer (TOFMS) to monitor progress, where the reactant gas was sampled by a sampling orifice and photoionized using pulsed, laser vacuum ultraviolet light before being analyzed by the TOFMS. Characterization of this setup has been carried out to identify the parameters that affect the time for “sampling,” which limits the fastest reactions that can be measured. A simple mathematical equation has been developed to correct for “sampling” delays (ksampling∼25, 000 s−1), which extends the range of rate coefficients to be measured in a kinetic mass spectrometry reactor to k′ < 7000 s−1. This method could be applied to any other kinetic mass spectrometry system where ksampling can be measured; an important advantage since it allows the study of reactions over a wider range of conditions (e.g., larger concentrations of reagents/products can be used to minimize the contribution from wall losses). The system can produce reliable kinetic data whether monitoring reactant decay or product growth even when the reaction and sampling processes are occurring on a similar timescale (k′ < 7000 s−1). Reproducible and reliable kinetic data have been obtained for the following reactions: SO + NO2 → products (R1), ClSO + NO2 → products (R2), where SO and ClSO were monitored under pseudo‐first‐order conditions, and HCO + O2 → CO + HO2 (R3), where CO was monitored by a [1+1] resonance enhanced ionization multiphoton ionization (REMPI) scheme with HCO reacting under pseudo–first‐order conditions. The limitations and potential developments of this setup are described. © 2011 Wiley Periodicals, Inc. Int J Chem Kinet 44: 532–545, 2012
A Potential Nanomedicine Consisting of Heparin‐Loaded Polysaccharide Nanocarriers for the Treatment of Asthma
Authors: Oyarzun‐Ampuero Felipe A. , Brea Jose , Loza Maria I. , Alonso Maria J. , Torres Dolores
Published: November 2011

A new nanomedicine consisting of chitosan/carboxymethyl‐β‐cyclodextrin loaded with unfractioned or low‐molecular‐weight heparin is described and its potential in asthma treatment is evaluated. The nanoparticles are prepared by ionotropic gelation showing a size that between 221 and 729 nm with a positive zeta potential. The drug association efficiency is higher than 70%. Developed nanosystems are stable in Hank's balanced salt solution at pH = 6.4, releasing the drug slowly. Ex vivo assays show that nanocarriers lead to an improvement of heparin preventing mast cell degranulation. These results agree with the effective cellular internalization of the fluorescently labeled nanocarriers, and suggest these nanomedicines as promising formulations for asthma treatment.

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Synthesis, Characterisation and in vitro Anti‐Angiogenic Potential of Dendron VEGF Blockers
Authors: Meikle Steven T. , Perugini Valeria , Guildford Anna L. , Santin Matteo
Published: November 2011

To overcome the lack of in vivo stability of certain peptides used in cancer treatment and to increase their retention time in the extracellular matrix of the target tissue, the anti‐angiogenic WHLPFKC sequence is synthesised at the uppermost branching generation of a poly(ε‐lysine) dendron. The root of these dendrons is designed to interact preferentially with macromolecules of the extracellular matrix, whilst the uppermost branching generation of the dendron increased the exposed density of the bioactive peptide. Bioactivity testing of the blockers is performed on HUVECs. The results show that the dendron tethered with VEGF blockers was still able to inhibit proliferation and angiogenesis. Their relatively larger structure did not prevent the interaction with VEGF.

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A Conducting Polymer/Protein Composite with Bactericidal and Electroactive Properties
Authors: Teixeira‐Dias Bruno , del Valle Luis J. , Aradilla David , Estrany Francesc , Alemán Carlos
Published: November 2011

Lysozyme, an enzyme with bactericidal activity over Gram‐positive bacteria cells, is incorporated into PEDOT to prepare films with high biological and electrochemical activity. Two different strategies are used: (1) PEDOT films are coated with a layer of enzyme, which was adsorbed on the surface; and (2) the lysozyme is added to the polymerization medium used for the preparation of the conducting polymer. The enzyme adsorbed at the surface of the polymer produces a biphasic system that retains the electrochemical properties of the conducting polymer but is not able to protect against bacterial growth. In contrast, the addition of lysozyme to the polymerization medium results in a homogeneous composite with high bactericidal and electrochemical activities.

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Biodegradable Blends From Plasticized Soy Meal, Polycaprolactone, and Poly(butylene succinate)
Authors: Reddy Murali M. , Mohanty Amar K. , Misra Manjusri
Published: November 2011

A synergistic effect of simultaneous plasticization and destructurization of soy protein in melt extrusion is studied using soy meal, glycerol, and urea. The combined effect of plasticization and destructurization yields thermoplastic soy meal (TSM) that is capable of chemical interactions with biodegradable polyesters. Melt‐compounded blends of TSM with biodegradable polyesters give new ductile bioplastics. The observed improvement in the properties of these blends might be due to two reason; the high elasticity of the destructured soy meal and the compatibility between the polyesters used. The synergistic effect of unfolding and destructurization of the protein by urea leads to high mobility in the protein chains of the soy meal.

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Fixed point theorems for a class of positive mixed monotone operators
Authors: Huang Chao‐Ya
Published: November 2011

In this paper, we study the fixed‐point theorems for a class of mixed monotone operators. Using Thompson's metric techniques and iterative methods, we construct monotone sequences which converge to the unique fixed point of the operator. Our results extend previous works of Guo 5 and Huang‐Huang‐Tsai 8. Applications to nonlinear second/fourth order boundary‐value problems are considered.
On the unimodality of power transformations of positive stable densities
Authors: Simon Thomas
Published: November 2011

Let Zα be a positive α‐stable random variable and \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$r\in {\mathbb {R}}.$\end{document} We show the existence of an unbounded open domain D in [1/2, 1] × ( − ∞, −1/2] with a cusp at (1/2, −1/2), characterized by the complete monotonicity of the function \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$F_{\alpha ,r}(\lambda ) = (\alpha \lambda ^\alpha -r)e^{-\lambda ^\alpha }\!\! ,$\end{document} such that \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$Z_\alpha ^r$\end{document} is unimodal if and only if (α, r)∉D.
On the non‐existence of free \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$ \mathcal {A}_d$\end{document}‐actions on products of spheres
Authors: Błaszczyk Zbigniew
Published: November 2011

We investigate the problem of existence of free alternating group actions on products of equidimensional spheres. Most notably, we prove that for a prime number p ≥ 7, the alternating group \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\mathcal {A}_{p+1}$\end{document} cannot act freely on a finite‐dimensional CW‐complex with the integral cohomology ring isomorphic to that of (Sn)p for any positive integer n. This extends previous results due to L. P. Plakhta.
Dopamine agonist use and the risk of heart failure
Authors: Renoux Christel , Dell'Aniello Sophie , Brophy James M. , Suissa Samy
Published: November 2011

Introduction

A potential risk of heart failure was recently observed in randomized trials of the dopamine agonist pramipexole. The extent of the risk with this and other dopamine agonists is unknown.

Methods

We used the UK General Practice Research Database (GPRD) to identify all users of anti‐parkinsonian drugs, 40–89 years of age, between 1997 and 2009. All incident heart failure cases were identified and classified as probable or possible on the basis of their treatment and mortality. Using a nested case–control approach, each case was matched with up to 10 controls selected among the cohort members. Incidence rate ratios (RR) of heart failure associated with the current use of dopamine agonists were estimated using conditional logistic regression, adjusted for covariates.

Results

The cohort included 26 814 users of anti‐parkinsonian drugs, with 783 newly diagnosed with heart failure during follow‐up (rate 8.7 per 1000 per year). The incidence rate of heart failure was increased with the current use of any dopamine agonist (RR = 1.58, 95% CI = 1.26–1.96), and particularly so for pramipexole (RR = 1.86, 95%CI = 1.21–2.85) and cabergoline (RR = 2.07, 95%CI = 1.39–3.07), compared with no use. The increase was not significant with ropinirole (RR = 1.23, 95%CI = 0.85–1.97) or pergolide (RR = 1.42, 95%CI = 0.95–2.12). Pramipexole was not associated with a significantly increased rate when compared with all other dopamine agonists collectively (RR = 1.28, 95%CI = 0.82–2.00).

Discussion

The use of dopamine agonists, especially pramipexole and cabergoline, is associated with an increased risk of heart failure. Copyright © 2011 John Wiley & Sons, Ltd.
Synthesis and characterization of rigid functional anionic polyelectrolytes: Block copolymers and star homopolymers
Authors: Rikkou‐Kalourkoti Maria , Kassi Eleni , Patrickios Costas S.
Published: November 2011

Seven cyclolinear polymers bearing the tertiary‐butyl α‐(hydroxymethyl)acrylate (TBHMA) ether dimer were prepared using reversible addition–fragmentation chain transfer (RAFT) polymerization. Of the seven polymers, five were cyclolinear homopolymers of the TBHMA ether dimer with different degrees of polymerization, one was an “arm‐first” star homopolymer, and the other was an amphiphilic linear copolymer based on the positively ionizable hydrophilic 2‐(dimethylamino)ethyl methacrylate (DMAEMA) and the TBHMA ether dimer. For comparison, two more polymers were prepared using RAFT polymerization where the TBHMA ether dimer was replaced by tertiary‐butyl methacrylate (tBuMA). In particular, an amphiphilic linear DMAEMA–tBuMA diblock copolymer and a tBuMA arm‐first star homopolymer were also synthesized. All polymers were characterized in terms of their molecular weights and composition using gel permeation chromatography and 1H NMR spectroscopy, respectively. Subsequently, the tertiary‐butyl groups of the TBHMA ether dimer units and those of the tBuMA units were cleaved by hydrolysis to yield carboxylic acid groups. The successful removal of the tertiary‐butyl groups was confirmed using 1H and 13C NMR and attenuated total reflectance‐Fourier transform infrared spectroscopies. The hydrolyzed (co)polymers exhibited pK values of the carboxylic acid groups of around 4.5, and glass transition temperatures, Tg, of around 200 °C, which were 50 °C higher than those of their nonhydrolyzed precursors. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Depressive symptoms among caregivers of colorectal cancer patients during the first year since diagnosis: a longitudinal investigation
Authors: Kim Youngmee , Carver Charles S. , Rocha‐Lima Caio , Shaffer Kelly M.
Published: November 2011

Objective

Few studies have examined prospectively and longitudinally depressive symptoms of family caregivers who provide care to colorectal cancer patients, and fewer have addressed ethnic minorities in this regard. This study investigated the relations of social support and caregiving stress with caregivers' depressive symptoms during the first year since the relative's diagnosis, as well as the role of ethnicity in such relations.

Methods

Seventy‐nine caregivers provided complete data at 2 months (T1), 6 months (T2), and 12 months (T3) after their relative's cancer diagnosis. Demographics and caregiving experiences were measured at T1. Depressive symptoms were assessed at T1 through T3.

Results

Greater caregiving stress and lack of social support were significant predictors of greater depressive symptoms. The adverse effect of caregiving stress was more pronounced among African American caregivers, whereas the beneficial effect of social support was more pronounced among White caregivers.

Conclusions

The findings highlight the importance of both caregiving stress and lack of social support early in caregivership. Findings also suggest that caregivers may benefit from programs tailored for their ethnicity. Copyright © 2011 John Wiley & Sons, Ltd.