bluuebunny/crossref_metadata_2025 huggingface dataset:
Human Merkel cell polyomavirus infection II. MCV is a common human infection that can be detected by conformational capsid epitope immunoassays
Authors: Tolstov Yanis L. , Pastrana Diana V. , Feng Huichen , Becker Jürgen C. , Jenkins Frank J. , Moschos Stergios , Chang Yuan , Buck Christopher B. , Moore Patrick S.
Published: April 2009

Merkel cell polyomavirus (MCV) is a newly‐discovered human tumor virus found in ∼80% of Merkel cell carcinoma (MCC). The rate of MCV infection among persons without MCC is unknown. We developed a MCV virus‐like particle (VLP) enzyme‐linked immunoassay (EIA) that does not cross‐react with human BK or murine polyomaviruses. Peptide mapping of the MCV VP1 gene and immunoblotting with denatured MCV VLP are less sensitive than the MCV EIA in detecting MCV antibodies suggesting antibody reactivity in this assay primarily targets conformational but not linear epitopes. Among MCC patients, all 21 (100%) patients tested with MCV‐positive tumors had high serum MCV IgG but not high MCV IgM levels. Only 3 of 6 (50%) MCC patients with MCV‐negative tumors were positive for MCV antibodies. Sera from most adults, including 107 of 166 (64%) blood donors, 63 of 100 (63%) commercial donors and 37 of 50 (74%) systemic lupus erythematosus patients, show evidence for prior MCV exposure. Age‐specific MCV prevalence was determined by examining a cross‐sectional distribution of 150 Langerhans cell histiocytosis (an unrelated neoplasm) patient sera. MCV prevalence increases from 50% among children age 15 years or younger to 80% among persons older than 50 years. We did not find evidence for vertical transmission among infants. Although past exposure to MCV is common among all adult groups, MCC patients have a markedly elevated MCV IgG response compared with control patients. Our study demonstrates that MCV is a widespread but previously unrecognized human infection. © 2009 UICC
Human Merkel cell polyomavirus infection I. MCV T antigen expression in Merkel cell carcinoma, lymphoid tissues and lymphoid tumors
Authors: Shuda Masahiro , Arora Reety , Kwun Hyun Jin , Feng Huichen , Sarid Ronit , Fernández‐Figueras María‐Teresa , Tolstov Yanis , Gjoerup Ole , Mansukhani Mahesh M. , Swerdlow Steven H. , Chaudhary Preet M. , Kirkwood John M. , Nalesnik Michael A. , Kant Jeffrey A. , Weiss Lawrence M. , Moore Patrick S. , Chang Yuan
Published: April 2009

Merkel cell polyomavirus (MCV) is a recently discovered human virus closely related to African green monkey lymphotropic polyomavirus. MCV DNA is integrated in ∼80% of Merkel cell carcinomas (MCC), a neuroendocrine skin cancer linked to lymphoid malignancies such as chronic lymphocytic leukemia (CLL). To assess MCV infection and its association with human diseases, we developed a monoclonal antibody that specifically recognizes endogenous and transfected MCV large T (LT) antigen. We show expression of MCV LT protein localized to nuclei of tumor cells from MCC having PCR quantified MCV genome at an average of 5.2 (range 0.8–14.3) T antigen DNA copies per cell. Expression of this putative viral oncoprotein in tumor cells provides the mechanistic underpinning supporting the notion that MCV causes a subset of MCC. In contrast, although 2.2% of 325 hematolymphoid malignancies surveyed also showed evidence for MCV infection by DNA PCR, none were positive at high viral copy numbers, and none of 173 lymphoid malignancies examined on tissue microarrays expressed MCV LT protein in tumor cells. As with some of the other human polyomaviruses, lymphocytes may serve as a tissue reservoir for MCV infection, but hematolymphoid malignancies associated with MCC are unlikely to be caused by MCV. © 2009 UICC
A case‐control study of cutaneous squamous cell carcinoma among Caucasian organ transplant recipients: The role of antibodies against human papillomavirus and other risk factors
Authors: Casabonne Delphine , Lally Aoife , Mitchell Liza , Michael Kristina M. , Waterboer Tim , Pawlita Michael , Imko‐Walczuk Beata , Wojnarowska Fenella , Proby Charlotte , Harwood Catherine , Newton Robert
Published: April 2009

A case‐control study was conducted in 140 people with histology proven cutaneous squamous cell carcinoma (SCC) and 454 controls, nested within 2 cohorts of organ transplant recipients (OTR) recruited in London and Oxford between 2002 and 2006. All participants had a skin examination, completed a questionnaire and had serum tested for antibodies against the L1 antigen of 34 HPV types using Luminex technology. SCC was more common in men than women (odds ratio [OR] = 1.7, 95% confidence interval [CI]: 1.1–2.8, p = 0.02) and in people with susceptibility to burn easily (OR = 3.0, 95%CI: 1.9–4.8; p < 0.001). The risk increased with increasing age (p‐trend < 0.001), increasing time since transplant (p‐trend < 0.001), increasing self‐reported number of sunburns as a child (p‐trend < 0.001) and with the presence of viral warts (p < 0.001). As expected, antibodies against HPV 16 were associated with a self‐reported history of an abnormal cervical smear among women (OR 5.1, 95%CI: 2.6–10.2) and antibodies against HPV 6 were associated with a self‐reported history of genital warts (OR 4.0, 95%CI: 2.2–7.2). However, no clear associations between any of the HPV types examined (including cutaneous betaHPVs) and SCC were identified. For example, the seroprevalence of HPV 5 was 15% among cases and 9% among controls (p = 0.09) and the seroprevalence of HPV 8 was 23% among cases and 21% among controls (p = 0.6). Nor was seropositivity to multiple types associated with SCC. These serological data do not provide evidence for a role for HPV in the aetiology of cutaneous SCC among OTR in two UK‐based populations. © 2009 UICC
Effect of astragaloside IV on the embryo‐fetal development of Sprague–Dawley rats and New Zealand White rabbits
Authors: Jiangbo Zhu , Xuying Wan , Yuping Zhu , Xili Ma , Yiwen Zheng , Tianbao Zhang
Published: April 2009

Astragaloside IV, a natural product purified from the Chinese medicinal herb Astragalus membranaceus (Fisch) Bge, is now being developed as a cardioprotective agent for treating cardiovascular diseases. In the present study developmental toxicity of astragaloside IV in Sprague–Dawley rats and New Zealand White rabbits was evaluated by intravenously administering astragaloside IV daily to rats at 0.25, 0.5 and 1.0 mg kg−1 on gestation days 6–15, and to rabbits at 0.5, 1.0 and 2.0 mg kg−1 daily on gestation days 6–18. Reproductive parameters were determined and fetuses were examined for external, visceral and skeletal malformations. There was significant difference in total weight gain during and after treatment between the control group and 1.0 mg kg−1 group in rats. The percentage of fetal deaths in 0.5 and 1.0 mg kg−1 rat groups was significantly higher than that of the control group, and higher in all treatment groups than in the control in rabbits. These results indicated that astragaloside IV was maternally toxic at 1.0 mg kg−1 in rats and fetotoxic at a dose higher than 0.5 mg kg−1, but devoid of teratogenic effects in rats and rabbits. In light of these findings it is perhaps prudent to advise caution to women who might use astragaloside IV to combat cardiovascular disease during pregnancy. Copyright © 2009 John Wiley & Sons, Ltd.
Diminished reproductive potential of male mice in response to selenium‐induced oxidative stress: Involvement of HSP70, HSP70‐2, and MSJ‐1
Authors: Kaushal Naveen , Bansal M. P.
Published: April 2009

The oxidative stress imposed by nutritional variations in selenium (Se) has plausible role in reproductive toxicology and affects the reproductive potential. Also, the expression of heat shock proteins (HSPs) is a highly regulated event throughout the process of spermatogenesis and is modulated by stressful stimuli. This prompted us to investigate the possibility that Se‐induced oxidative stress may affect the fertility status by altering the expressions of the constitutive and inducible HSP70 proteins, having crucial role in spermatogenesis. Different Se status‐deficient, adequate, and excess, male Balb/c mice were created by feeding yeast‐based Se‐deficient diet (group I) and deficient diet supplemented with Se as sodium selenite at 0.2 and 1 ppm Se (group II and III) for a period of 8 weeks. After completion of the diet‐feeding schedule, a significant decrease in the Se and glutathione peroxidase (GSH‐Px) levels was observed in the Se‐deficient group (I), whereas Se‐excess group (III) demonstrated an increase. Increased levels of reactive oxygen species, malondialdehyde, and alterations in the redox status in both groups I and III indicated oxidative‐stressed conditions. There was an overall reduced fertility status in mice supplemented with Se‐deficient and Se‐excess diet. The mRNA and protein expression of HSP70 was found to be elevated in these two groups, whereas the expression patterns of HSP70‐2 and MSJ‐1 demonstrated a reverse trend. In vitro CDC2 kinase assay showed reduced kinase activity in group I and group III. These findings suggest that Se‐induced oxidative stress by differentially regulating various HSP70s can affect its downstream factors having crucially important role in differentiation of germ cells and completion of spermatogenesis. Therefore, it can provide an insight into the mechanism(s) by which the oxidative stress–induced reproductive toxicity can lead to increased apoptosis/growth arrest and infertility. This will thus add new dimensions to the molecular mechanism underlying the human male infertility and open new vistas in the development of various chemo‐preventive methods. © 2009 Wiley Periodicals, Inc. J Biochem Mol Toxicol 23:125–136, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20276
Enhanced enzymatic hydrolysis of rice straw pretreated by alkali assisted with photocatalysis technology
Authors: Niu Kun , Chen Peng , Zhang Xu , Tan Wen‐Song
Published: April 2009

BACKGROUND: The fermentable sugars in lignocellulose are derived from cellulose and hemicellulose, which are not readily accessible to enzymatic hydrolysis because of their biological resistance, so that pretreatment of lignocellulose is needed for this process. In this work, a novel lignocellulose pretreatment method using alkali solution assisted by photocatalysis was investigated.

RESULTS: The reaction conditions of nano‐TiO2 dosage and photocatalysis time were optimized at 2 g L−1 and 1 h, respectively. After pretreatment under these conditions, cellulose in rice straw was increased from 37.5% to 71.5%, and lignin decreased from 18.5% to 9.0%. The results of X‐ray diffraction (XRD), Fourier transform infrared (FT‐IR) and scanning electron microscopy (SEM) analysis showed that the physical properties and microstructure of the straw were changed by this pretreatment, which favored the following enzymatic hydrolysis. The enzymatic hydrolysis rate of the straw pretreated using this technology was verified to be 73.96%, which was 2.56 times higher than that obtained with the alkali procedure.

CONCLUSION: The proposed photocatalysis pretreatment technology was more efficient at degrading the lignin and hemicellulose in rice straw than alkali pretreatment, making it more readily available for the following enzymatic hydrolysis process. Copyright © 2009 Society of Chemical Industry
Edge disjoint Steiner trees in graphs without large bridges
Authors: Kriesell Matthias
Published: April 2009

A set A of vertices of an undirected graph G is called k‐edge‐connected in G if for all pairs of distinct vertices a, b∈A, there exist k edge disjoint a, b‐paths in G. An A‐tree is a subtree of G containing A, and an A‐bridge is a subgraph B of G which is either formed by a single edge with both end vertices in A or formed by the set of edges incident with the vertices of some component of G − A. It is proved that (i) if A is k·(ℓ + 2)‐edge‐connected in G and every A‐bridge has at most ℓ vertices in V(G) − A or at most ℓ + 2 vertices in A then there exist k edge disjoint A‐trees, and that (ii) if A is k‐edge‐connected in G and B is an A‐bridge such that B is a tree and every vertex in V(B) − A has degree 3 then either A is k‐edge‐connected in G − e for some e∈E(B) or A is (k − 1)‐edge‐connected in G − E(B). © 2009 Wiley Periodicals, Inc. J Graph Theory 62: 188–198, 2009
Classical eigenvalue mode‐spectrum analysis of multiple‐ridged rectangular and circular waveguides for the design of narrowband waveguide components
Authors: Yu Seng Yong , Bornemann Jens
Published: April 2009

A classical eigenvalue mode‐spectrum analysis of waveguides with multi‐ridged cross sections is presented and applied to the design of narrowband waveguide components in rectangular and circular waveguide technology. Modifications of the modes of the empty waveguide enclosures are used as expansion functions and lead to a classical, real and symmetric eigenvalue problem. A simple yet efficient constraint function is introduced to satisfy boundary conditions for TM modes. The number and locations of ridges positioned in a regular rectangular or circular waveguide enclosure is arbitrary. Measurements and comparisons with results from existing full‐wave modeling tools and commercially available field solvers verify the correctness and flexibility of the approach. Copyright © 2009 John Wiley & Sons, Ltd.
Relationships between tropical cyclones and heavy rainfall in the Carolina region of the USA
Authors: Konrad Charles E. , Perry L. Baker
Published: April 2009

A strong association exists between exceptionally heavy rainfall and the movement of tropical cyclones (i.e. tropical depressions, tropical storms, and hurricanes) across the Carolina region of the USA. There is much variability, however, in the precipitation totals associated with each tropical cyclone. This variability is at least partially tied to various interactions between mid‐latitude features and the moisture plume that is advected around the tropical cyclone. In the first part of this study, a 55‐year precipitation events climatology is constructed that quantifies the influence of tropical cyclones on precipitation events with varying return intervals. In particular, it shows that the majority of the heaviest precipitation events in the eastern three‐quarters of the region are associated with tropical cyclones. In the second part of this study, a synoptic climatology is developed that reveals the relationships between precipitation totals and various atmospheric variables. The variables include the speed of movement, size, and strength of the tropical system as well as the relative position and strength of various synoptic features surrounding the tropical system. These synoptic features include the location of fronts, regions of upper level divergence and areas of high water vapor contents in the atmosphere. A tree regression model is used to develop a classification that summarizes these multivariate relationships. Four classes of tropical cyclones are identified that effectively differentiate tropical cyclones that produce relatively light versus extraordinarily heavy rainfall. Copyright © 2009 Royal Meteorological Society
Multifractal analysis of measure representation of flood/drought grade series in the Yangtze Delta, China, during the past millennium and their fractal model simulation
Authors: Zhang Qiang , Yu Zu‐Guo , Xu Chong‐Yu , Anh Vo
Published: April 2009

Based on reconstructed flood/drought grade series, IFS (iterated function systems) and RIFS [(recurrent) iterated function systems] models were used to reconstruct their measure representations. The goodness‐of‐fit of the simulation indicated good performance of IFS and RIFS models in simulation of the measure representations of the historical flood/drought grade series in the Yangtze Delta. Multifractal properties of the measures of the flood/drought grade series were analyzed using multifractal detrended fluctuation analysis (MF‐DFA) technique. The DFA1 exponents of 0.6348 ± 0.013 and 0.7215 ± 0.013 indicated that the measures of the flood/drought grade series of the Yangtze Delta were characterized by long memory or persistence. Furthermore, the h(q) curves of the measure representations indicated that the measure representations of the flood/drought grade series in the Yangtze Delta were multifractal measures. The finding of this paper highlights possibility of prediction for future climatic changes based on historical records in the Yangtze Delta region. Copyright © 2009 Royal Meteorological Society
Coherent anti‐Stokes Raman scattering microscopy within a microcavity with parallel mirrors
Authors: Marrocco Michele , Nichelatti Enrico
Published: April 2009

Coherent anti‐Stokes Raman scattering (CARS) microscopy, or micro‐CARS, is becoming more and more popular to identify chemical species with notable three‐dimensional resolution. In view of this important application, the present work tries to extend the analysis of cavity effects that are well known in other branches of linear and nonlinear optics. In particular, the CARS process taking place within a Fabry‐Pérot microcavity (with mirror spacing on the order of the anti‐Stokes wavelength) is here examined. Two theoretical cavity models are used and found interchangeable as to the description of the typical phenomenology of enhancement and inhibition expected for the electromagnetic confinement induced by the boundary conditions. These phenomena are responsible of strong alterations in the spatial distribution of micro‐CARS, and instructive examples are shown for spherical Raman scatterers of different sizes. To sum them up, the signal enhancement occurs in correspondence of pronounced narrowing and elongation of the emission lobes surrounding the optical axis (coincident with the propagation direction of the collinear laser beams). Conversely, the inhibition is characterized by the ejection of radiation at large angles (with respect to the optical axis) for those wavelengths that do not respect the cavity tuning adjusted on the given anti‐Stokes wavelength. The different angular properties of spectrally separated components of CARS signals are then proven useful for the amplification of the contrast defining the quality of CARS imaging. In the end, amplifications of one or two orders of magnitude are calculated depending on different experimental conditions. Limits and future developments of the present approach are discussed in the conclusions. Copyright © 2009 John Wiley & Sons, Ltd.
Study of two different cold restructuring processes using two different qualities of hake (Merluccius capensis) muscle, with addition of microbial transglutaminase
Authors: Moreno Helena M , Carballo José , Javier Borderías A
Published: April 2009

BACKGROUND: Microbial transglutaminase (MTGase) can improve the mechanical and functional properties of restructured fish products without the need of thermal gelation. The present study seeks to determine whether, for different setting times, MTGase activity in restructured hake muscle made with pieces or with homogenised muscle can be affected by the quality of the protein in the raw materials.

RESULTS: As regards mechanical properties, samples of both qualities subjected to the two different processes attained a suitable consistency after setting for 24 h at 5 °C. The quality of the protein in the sample is important when pieces are used for restructuring, but not when sample is homogenised. Also, there were strong correlations between residual MTGase activity up to 12 h and mechanical properties and electrophoretic band density. Water binding capacity (WBC) was not significantly altered by MTGase addition.

CONCLUSION: The experimental combination of 10 g kg−1 of MTGase, 15 g kg−1 of sodium chloride and 7.5 g kg−1 of sodium caseinate was suitable for the production of minimally processed raw restructured fish products made with two different qualities of fish protein and two different restructuring processes. In the restructured products made with pieces, the protein quality significantly affected final properties, but in finely homogenised product the protein quality was less important. Copyright © 2009 Society of Chemical Industry
Enantiomeric separation of acidic compounds by nano‐liquid chromatography with methylated‐β‐cyclodextrin as a mobile phase additive
Authors: Rocco Anna , Fanali Salvatore
Published: April 2009

Some racemic nonsteroidal anti‐inflammatory drugs, namely naproxen, indoprofen, ketoprofen, flurbiprofen, carprofen, cicloprofen, flunoxaprofen and suprofen were separated into their enantiomers by nano‐LC. Chiral recognition was achieved adding to the mobile phase heptakis (2,3,6‐tri‐O‐methyl)‐β‐cyclodextrin (TM‐β‐CD). Capillary columns of 100 μm id, packed with different RP particles were used for experiments. Effect of experimental parameters such as mobile phase composition, stationary phase type and length of packed capillary column on retention factor and chiral resolution of analytes were studied. The stationary phase type played a very important role in the enantiorecognition process. Best results in terms of highest enantioresolution factor and largest number of separated enantiomers were obtained reducing the particles size to 3 μm with RP18 stationary phase. Most favourable mobile phase for enantiodiscrimination was obtained using relatively low concentrations of ACN (30%, v/v), 30 mM of TM‐β‐CD and pH value of 3.0. The retention time of all studied enantiomers decreased by increasing the CD derivative concentration. The retention factors of selected studied compounds, specifically flurbiprofen, naproxen and suprofen, were measured employing TM‐β‐CD concentrations in the range 0–40 mM. Assuming a 1:1 enantiomer/CD ratio, the apparent association constants of the studied enantiomers were calculated.
Selectivity of arginine chromatography in promoting different interactions using synthetic oligonucleotides as model
Authors: Sousa Ângela , Sousa Fani , Queiroz João A.
Published: April 2009

Arginine has been effectively used in several chromatography methodologies to improve recovery, resolution, and to suppress aggregation. Recently, arginine chromatography was used to fully separate supercoiled and open circular plasmid DNA isoforms. The specific recognition of supercoiled plasmid isoform by arginine was hypothesised to be due to the ability of arginine matrix to be involved in complex interactions that are partly dependent on the conformation of the DNA molecule. In light of these considerations a study was conducted to understand the several interactions that a DNA molecule can promote with the arginine support, in accordance with the chromatographic conditions established. Consequently, knowing the ideal conditions to promote the specific interactions, it could be possible to perform a more targeted and efficient purification. This work describes the chromatography of oligonucleotides with sizes up to 30 bases on the arginine‐agarose gel. The effect of several conditions like hydrophobic character of the individual bases, molecular mass of the oligonucleotides, presence of secondary structures, temperature and elution buffer composition (salt and arginine supplemented buffer) was investigated. According to previous atomic data referent to possible interactions between amino acids and DNA nucleotides, arginine can preferentially interact with guanine by hydrogen bond, but other interactions (ionic interactions, van der Waals contacts, water mediated bonds) may also be present and become dominant depending on the conditions used. The results also revealed that the application of arginine in the elution buffer led to an effective elution of oligonucleotides from the arginine chromatographic support by a competition strategy. In general, it was suggested that the affinity interaction promoted by the arginine support is responsible for the specific recognition of particular oligonucleotide bases, involving multiple interactions.
Nucleic acid aptamer molecular recognition principles and application in liquid chromatography and capillary electrophoresis
Authors: Peyrin Eric
Published: April 2009

Nucleic acid aptamers isolated from the systematic evolution of ligands by exponential enrichment (SELEX) have the capacity to recognize various classes of target molecules with high affinity and specificity. In this context, the development of aptamer‐based molecular recognition tools has become a very interesting and promising analytical strategy during the last few years. In this review, the molecular recognition features of aptamers as well as the key factors for their practical applicability to the chromatographic and capillary electrophoretic fields are summarized.
The psychological health of contractors working in war zones
Authors: Feinstein Anthony , Botes Maggie
Published: April 2009

This study examines the psychological health of contractors working in war zones. Seventy‐nine contractors completed an Internet‐based psychiatric assessment. The sample was exclusively male with a mean age of 43 (SD = 7) years. The number of contractors whose scores exceeded the cutoff points for depression, psychological distress, and excessive weekly alcohol consumption were 15 (20%), 21 (28%), and 13 (17%), respectively. A third of contractors had posttraumatic stress disorder (PTSD) scores in the moderate to severe range. Approximately 10% of contractors had employer‐organized access to psychological help following deployment. This study provides the first empirical data showing that a significant minority of contractors working in war zones are psychologically distressed and not receiving therapy.
Disulfide‐Crosslinked Electrospun Poly(γ‐glutamic acid) Nonwovens as Reduction‐Responsive Scaffolds
Authors: Yoshida Hiroaki , Klinkhammer Kristina , Matsusaki Michiya , Möller Martin , Klee Doris , Akashi Mitsuru
Published: April 2009

Novel water‐insoluble, and reduction‐responsive nonwoven scaffolds were fabricated from γ‐PGA and tested in cell culture. An electrospinning method was developed to produce scaffolds of fibers with diameters of 0.05–0.5 µm. Crosslinking of the fibers with cystamine in the presence of EDC resulted in water‐insoluble γ‐PGA nonwovens with disulfide crosslinkages. These crosslinked fibers were easily decomposed under physiological conditions using L‐cysteine, a biocompatible reductant. In vitro experiments with mouse L929 fibroblasts showed good adhesion onto γ‐PGA‐SS fiber matrices and excellent cell proliferation. These γ‐PGA‐SS nonwovens can be used as novel biocompatible and biodegradable scaffolds with reduction‐responsiveness for biomedical or tissue engineering applications.

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Thermosensitive Micelles Based on Folate‐Conjugated Poly(N‐vinylcaprolactam)‐block‐Poly(ethylene glycol) for Tumor‐Targeted Drug Delivery
Authors: Prabaharan Mani , Grailer Jamison J. , Steeber Douglas A. , Gong Shaoqin
Published: April 2009

Thermosensitive PNVCL‐b‐PEG block copolymer coupled with folic acid was prepared as an anti‐cancer drug carrier. This polymer self‐assembled into stable micelles in aqueous solutions at above 33 °C. At 37 °C, the release profile of PNVCL‐b‐PEG‐FA micelles showed a slower and more controlled release of the entrapped 5‐FU than that at 25 °C. The blank and 5‐FU‐loaded PNVCL‐b‐PEG‐FA micelles did not induce remarkable cytotoxicity against the EA.hy 926 human endothelial cell line; however, 5‐FU‐loaded PNVCL‐b‐PEG‐FA micelles showed a cytotoxicity effect against 4T1 mouse mammary carcinoma cells due to the availability of loaded anti‐cancer drugs delivered to the inside of the cancer cells by the folate‐receptor‐mediated endocytosis process.

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A One‐Pot Approach to Novel Cross‐Linked Polyphosphazene Microspheres with Active Amino Groups
Authors: Zhang Peng , Huang Xiaobin , Fu Jianwei , Huang Yawen , Zhu Yan , Tang Xiaozhen
Published: April 2009

Highly cross‐linked microspheres bearing active amino groups on the surface have been successfully synthesized via a single‐step precipitation polymerization of hexachlorocyclotriphosphazene (HCCP) with 4,4′‐diaminodiphenyl ether (ODA) in acetonitrile medium without any added surfactant. The active microspheres were characterized by Fourier transform infrared (FTIR), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and differential scanning calorimetry (DSC). The results revealed that the active microspheres had clean surfaces and they were in the size of micrometer range, varying from 0.5 to 2.5 µm. The accessibility of the surface amino groups to further functionalization was confirmed by the reaction of these groups with benzoxy chloride. Interestingly, the content of amino groups can be easily tailored through changing the molar ratio of HCCP to ODA. The effects of the concentration of HCCP and the monomer ratios on the morphology were also discussed.

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Novel Low Bandgap EDOT‐Naphthalene Bisimides Conjugated Polymers: Synthesis, Redox, and Optical Properties
Authors: Wei Yufeng , Zhang Qing , Jiang Yadong , Yu Junsheng
Published: April 2009

Low band‐gap conjugated polymers based on naphthalene bisimide (NBI) and 3,4‐ethylenedioxythiophene (EDOT) were synthesized by Stille cross‐coupling reaction. The alternating conjugated poly(EDOT‐NBI) (P1) and random poly(EDOT‐NBI) (P2) are both solution‐processable due to the existence of bulky 2,6‐diisopropylphenyl substituent. Their optical and electrochemical properties were characterized. P1 and P2 films show optical band gaps of 1.75 and 1.38 eV estimated from UV‐Vis absorption spectra. Cyclic voltammograms of both polymers display reversible reduction peaks with onset reduction potentials at −0.55 V for P1 and −0.61 V for P2, which correspond to the electron affinity (EA) values (LUMO energy level) of 3.85 and 3.79 eV, respectively. The ionization potential (IP, HOMO level) values of 5.60 eV for P1 and 5.17 eV for P2 were also calculated by combining solid‐state optical and electrochemical data. A double heterojunction device was fabricated. It exhibits an open circuit voltage of 0.30 V and average power conversion efficiency of 0.15%.

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Macromol. Chem. Phys. 8/2009
Authors: Nasrullah Mohammed J. , Webster Dean C.
Published: April 2009

Cover: The parallel synthesis of polymers permits the study of several variables simultaneously in a single experiment. In this example, the effect of target molecular weight and reaction time on molecular weight development for 24 polymers synthesized using atom‐transfer radical polymerization (ATRP) was determined in a single experiment. Further details can be found in the article by M. J. Nasrullah, D. C. Webster* on page 640.
Macromol. Mater. Eng. 4/2009
Authors: Kunzelman Jill , Gupta Mohit , Crenshaw Brent R. , Schiraldi David A. , Weder Christoph
Published: April 2009

Cover: The picture summarizes a new strategy for the design of mechanochromic polymers. Polyesters that comprise oligo(phenylene vinylene) sensor chromophores are reported. Compression leads to dispersion of the originally aggregated sensor moieties, concomitant with pronounced changes of the material's optical properties. Further details can be found in the article by J. Kunzelman, M. Gupta, B. R. Crenshaw, D. A. Schiraldi,* and C. Weder* on page 244.
Spontaneous Self‐Assembly of a Mono‐Component Polyimide Bearing Terminal Hydrogen‐Bonding Sites in a Single Solvent
Authors: Liu Xikui , Liu Junzhi , Jiang Ming
Published: April 2009

A unique example of macromolecular self‐assembly, where a mono‐component homopolyimide bearing carboxy end‐groups spontaneously forms nanopartilces with novel dimple‐like morphology in a single good solvent, is presented. The self‐assembly process is dramatically affected by the solution concentration and the temperature. It is proposed that such an unexpected self‐assembly behavior is a synergistic result of the self‐complementary hydrogen bonding between carboxy end‐groups and the propensity to parallel packing of polyimide chains through aromatic interactions.

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Recent advances in mass spectrometry analysis of phenolic endocrine disruptors and related compounds
Authors: Gallart‐Ayala H. , Moyano E. , Galceran M.T.
Published: April 2009

This article reviews recent literature on current methodologies based on chromatography coupled to mass spectrometry to analyze phenolic compounds with endocrine‐disrupting capabilities. For this review we chose alkylphenol ethoxylates, bisphenol A, bisphenol F, and their degradation products and halogenated derivatives, which are considered important environmental contaminants. Additionally, some related compounds such as bisphenol diglycidylethers were included. Growing attention has been paid to the mass spectrometric characterization of these compounds and the instrumentation and strategies used for their quantification and confirmation. The current use of gas chromatography–mass spectrometry (GC–MS) and liquid chromatography–mass spectrometry (LC–MS) methodologies with different mass spectrometers and ionization and monitoring modes is discussed. Practical aspects with regards to the use of these analytical techniques, such as derivatizing reagents in GC–MS, ion suppression in LC–MS, and the most problematic aspects of quantification, are included in the discussion. © 2009 Wiley Periodicals, Inc., Mass Spec Rev 29:776–805, 2010
Macromol. Theory Simul. 3/2009
Authors: Qu Li‐Jian , Jin Xigao , Liao Qi
Published: April 2009

Cover: Numerical self‐consistent field (SCF) theory have revealed the dependences of the structures and the conformations of the Cylindrical polyelectrolyte brushes (CPBs) in dilute solution on the salt concentration, the grafting density, and the chain length. The SCF results give deep insight into the non‐power behaviors of the CPBs which is beyond the application scope of the scaling theory. Further details can be found in the article by L.‐J. Qu, X. Jin, Q. Liao* on page 162.
The use of a color coded probability scale to interpret smell tests in suspected parkinsonism
Authors: Silveira‐Moriyama Laura , Petrie Aviva , Williams David R. , Evans Andrew , Katzenschlager Regina , Barbosa Egberto R. , Lees Andrew J.
Published: April 2009

Smell identification tests (SITs) have been suggested as useful in the differential diagnosis of Parkinson's disease (PD). We have applied the 40 item University of Pennsylvania SIT (UPSIT‐40) and/or the 16 item SIT from Sniffin Sticks (SS‐16) to 193 nondemented PD patients and 157 controls and used logistic regression analysis to associate the SIT result with the probability of an individual patient having PD (“PD probability”). Reliability measures (95% CI) using the clinical diagnosis as a gold standard and a dichotomized result of the smell test into high (50% or more) or low (<50%) “PD probability” were: sensitivity 85.0% (78.8–89.7%), specificity 84.6% (77.3–89.9%) for the UPSIT‐40; sensitivity 90.4% (83.5–94.7%), specificity 85.5% (76.2–91.7%) for the SS‐16. Based on these findings we have created color coded visual tools (PD probability rulers) and applied them to 39 clinically uncertain parkinsonian syndromes (CUPS) patients who had been investigated with dopamine transporter SPECT scanning using [123‐I]‐FP‐CIT SPECT (DaTSCAN) for suspected Parkinson's disease. In 32 of 36 CUPS cases (88.9%, kappa = 0.72) the probability ruler predicted the result of the DaTSCAN. We suggest smell tests could be used routinely in challenging cases where there is diagnostic uncertainty and help inform decision making relating to the need for neuro imaging. © 2009 Movement Disorder Society
Randomized controlled trial of memantine in dementia associated with Parkinson's disease
Authors: Leroi Iracema , Overshott Ross , Byrne E. Jane , Daniel Emily , Burns Alistair
Published: April 2009

The objective of this study is to investigate the safety and tolerability of memantine, a glutamatergic modulator, in patients suffering from dementia associated with Parkinson's disease (PDD), an increasingly common complication of PD. This was a 22‐week trial of 25 participants with a DSM‐IV diagnosis of PDD who were randomized to either placebo or 20 mg/day of memantine. Memantine was well tolerated by participants at 20 mg/day dosing. No participant was withdrawn due to memantine‐related adverse events. Six weeks after drug withdrawal, a significantly greater proportion (P = 0.04) of memantine‐treated participants deteriorated globally compared with those treated with placebo. These findings suggest that continued treatment with memantine may be needed to maintain global level of functioning over time. Based on the findings of this pilot study, memantine is safe and very well‐tolerated in PDD. © 2009 Movement Disorder Society
Parameter Estimation in a Simplified MWD Model for HDPE Produced by a Ziegler‐Natta Catalyst
Authors: Thompson Duncan E. , McAuley Kim B. , McLellan P. James
Published: April 2009

A simplified steady‐state model to predict MWDs of ethylene/butene and ethylene/hexene copolymers produced industrially using heterogeneous Z‐N catalysts is developed. Estimability analysis is used to guide model simplification and to determine which parameters can be estimated using the available data. Scaling of response variables and parameters using information about their uncertainties ensures that appropriate results are obtained from the estimability analysis. Parameter estimates are obtained to provide good predictions of the measured MWDs. Although the parameter values obtained are specific to the Z‐N catalyst of our industrial sponsor, the method should be useful for parameter estimation and model simplification in other catalytic polymerization systems.

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Electrophysiological studies in a mouse model of Schwartz–Jampel syndrome demonstrate muscle fiber hyperactivity of peripheral nerve origin
Authors: Echaniz‐Laguna Andoni , Rene Frédérique , Marcel Christophe , Bangratz Marie , Fontaine Bertrand , Loeffler Jean‐Philippe , Nicole Sophie
Published: April 2009

Schwartz–Jampel syndrome (SJS) is an autosomal‐recessive condition characterized by muscle stiffness and chondrodysplasia. It is due to loss‐of‐function hypomorphic mutations in the HSPG2 gene that encodes for perlecan, a proteoglycan secreted into the basement membrane. The origin of muscle stiffness in SJS is debated. To resolve this issue, we performed an electrophysiological investigation of an SJS mouse model with a missense mutation in the HSPG2 gene. Compound muscle action potential amplitudes, distal motor latencies, repetitive nerve stimulation tests, and sensory nerve conduction velocities of SJS mice were normal. On electromyography (EMG), neuromyotonic discharges, that is, bursts of motor unit action potentials firing at high rates (120–300 HZ), were constantly observed in SJS mice in all muscles, except in the diaphragm. Neuromyotonic discharges were not influenced by general anesthesia and disappeared with curare administration. They persisted after complete motor nerve section, terminating only with Wallerian degeneration. These results demonstrate that perlecan deficiency in SJS provokes a neuromyotonic syndrome. The findings further suggest a distal axonal localization of the generator of neuromyotonic discharges. SJS should now be considered as an inherited disorder with peripheral nerve hyperexcitability. Muscle Nerve, 2009
Urinary nerve growth factor is a better biomarker than detrusor wall thickness for the assessment of overactive bladder with incontinence
Authors: Kuo Hann‐Chorng , Liu Hsin‐Tzu , Chancellor Michael B.
Published: April 2009

Purpose

To compare the differences in urinary nerve growth factor (NGF) and detrusor wall thickness (DWT) between patients with overactive bladder (OAB) and controls to evaluate their suitability as biomarkers in OAB.

Materials and Methods

A total of 81 patients including normal controls (n = 28), patients with OAB dry (n = 28) and OAB wet (n = 25) were enrolled in this study. Videourodynamic study was performed in 79 patients after confirmation of symptomatic classification by 3‐day voiding diary. Urine NGF and DWT measurements were performed at full bladder and urge to void after natural‐filling or catheter‐filling during videourodynamic study. Urinary NGF level was measured by the ELISA method and DWT was measured by trans‐abdominal ultrasound. These two parameters were compared among different symptomatic and urodynamic subgroups.

Results

DWT was not significantly different among subgroups at 250 ml bladder volume. Although patients with OAB wet had a significantly greater DWT at the maximal bladder volume, this difference was not significant from controls after correction of the volume factor. By contrast, urinary NGF levels were significantly increased in patients with OAB wet and those with urodynamic detrusor overactivity. However, elevated NGF levels in OAB wet were found only after natural‐filling and not after catheter‐filling.

Conclusions

Urinary NGF level in natural‐filling urine sample is a better biomarker for assessment of OAB wet compared to DWT. Patients with OAB dry or hypersensitive bladder did not have an elevated urinary NGF level. Urine samples from catheter‐filling do not have a detectably high NGF levels. Neurourol. Urodynam. 29:482–487, 2010. © 2009 Wiley‐Liss, Inc.
Numerical analysis of growing crack problems using particle discretization scheme
Authors: Wijerathne M. L. L. , Oguni Kenji , Hori Muneo
Published: April 2009

This paper presents the particle discretization scheme (PDS) to analyze brittle failure of solids. The scheme uses characteristic functions of Voronoi and Delaunay tessellations to discretize a function and its derivatives, respectively. A discretized function has numerous discontinuities so that these discontinuities are utilized as a candidate of crack path segment in modeling propagating cracks, without making any extra computation to accommodate new displacement discontinuities. When the scheme is implemented to a finite element method (FEM), the resulting stiffness matrix coincides with the one that is obtained by using linear elements. The accuracy of computing a stress intensity factor at a crack tip is examined. It is shown that the accuracy is better than that of a FEM with linear elements when the rotational degree of freedom is included in discretizing displacement functions. Three three‐dimensional growing crack problems are solved by means of the PDS and the results are presented. Copyright © 2009 John Wiley & Sons, Ltd.
Optimal design of simply supported columns subject to distributed axial load and stress constraint
Authors: Adali Sarp , Cagdas Izzet U.
Published: April 2009

The optimum designs are given for columns, which are simply supported and under distributed and concentrated axial loads. The objective is to maximize the buckling load subject to volume and maximum stress constraints. The area of the minimum cross‐section under a stress constraint is not known a priori as it depends on the maximum buckling load which in turn depends on the optimum shape. This minimum cross‐sectional area is computed as part of an iterative procedure. An iterative solution method is developed based on finite elements and the results are obtained for n=1, 2, 3, defined as I =αnAn with I being the moment of inertia, and A the cross‐sectional area. Numerical results show that the optimal areas become larger in the direction of the distributed load. Results are given for uniformly and triangular distributed loads, which are shown to have distinct effects on the optimal column shape. Copyright © 2009 John Wiley & Sons, Ltd.
The effect of shear on mechanical properties and orientation of HDPE/mica composites obtained via dynamic packing injection molding (DPIM)
Authors: Xiang Yufang , Hou Zaichuan , Su Run , Wang Ke , Fu Qiang
Published: April 2009

The interfacial interaction and orientation of filler play important roles in the enhancement of mechanical performances for polymer/inorganic filler composites. Shear has been found to be a very effective way for the enhancement of interfacial interaction and orientation. In this work, we will report our recent efforts on exploring the development of microstructure of high density polyethylene (HDPE)/mica composites in the injection‐molded bars obtained by so‐called dynamic packing injection molding (DPIM), which imposed oscillatory shear on the melt during the solidification stage. The mechanical properties were evaluated by tensile testing and dynamic mechanical analysis (DMA), and the crystal morphology, orientation, and the dispersion of mica were characterized by scanning electron microscopy and two‐dimensional wide‐angle X‐ray scattering. Compared with conventional injection molding, DPIM caused an obvious increase in orientation for both HDPE and mica. More importantly, better dispersion and epitaxial crystallization of HDPE was observed on the edge of the mica in the injection‐molded bar. As a result, increased tensile strength and modulus were obtained, accompanied with a decrease of elongation at break. The obtained data were treated by Halpin–Tsai model, and it turned out that this model could be also used to predict the stiffness of oriented polymer/filler composites. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis and characterization of polypyrrole nanofibers with different dopants
Authors: Goel Shubhra , Mazumdar Nasreen A. , Gupta Alka
Published: April 2009

Nanostructures of polypyrrole (PPy) were synthesized in the presence of different dopants including hydrochloric acid (HCl), ferric chloride (FeCl3), p‐toluene sulfonic acid (p‐TSA), camphor sulfonic acid (CSA), and polystyrene sulfonic acid (PSSA), using a simple interfacial oxidative polymerization method. The method is a reliable non‐template approach with relatively simple instrumentation, ease of synthesis, and economic viability for synthesizing PPy nanostructures. Morphology of synthesized PPy structures was investigated using scanning electron microscopy (SEM) and transmission electron microscopy (TEM), which indicate the formation of one‐dimensional (1D) nanofibers with average diameter of 75–180 nm. Energy dispersive spectrum (EDS) of the PPy nanofibers indicates the attachment of the dopants to the PPy backbone; the fact is further confirmed by the Fourier transform infrared (FTIR) spectra of PPy nanostructures. Thermal stabilities of the nanostructures explored using thermal gravimetric analysis (TGA) follow the order PPy‐p‐TSA > CSA > HCl > FeCl3 > PSSA. It is noticed that the electrical conductivity (EC) of PPy nanostructures depends upon the nature of dopant (PPy‐p‐TSA > CSA > HCl > FeCl3 > PSSA), PPy‐p‐TSA nanofibers showing the highest EC of 6 × 10−2 Scm−1. Copyright © 2009 John Wiley & Sons, Ltd.
Increased RANKL expression is related to tumour migration and metastasis of renal cell carcinomas
Authors: Mikami Shuji , Katsube Ken‐ichi , Oya Mototsugu , Ishida Masaru , Kosaka Takeo , Mizuno Ryuichi , Mochizuki Satsuki , Ikeda Tohru , Mukai Makio , Okada Yasunori
Published: April 2009

Receptor activator of NF‐κB ligand (RANKL) and its receptor, receptor activator of NF‐κB (RANK), play a key role in osteoclastogenesis, and osteoprotegerin (OPG) acts as a decoy receptor for RANKL. We investigated the role of the RANKL–RANK–OPG system in renal cell carcinomas (RCCs), which frequently metastasize to bones. Real‐time quantitative PCR revealed that RANKL mRNA expression was higher in clear cell RCCs than in papillary and chromophobe RCCs. Similarly, RANKL protein expression level in clear cell RCCs was higher than that in papillary and chromophobe RCCs, showing positive correlations with the primary tumour stage and distant metastasis. There was no significant association between the expression level of RANK, OPG and histological subtypes of RCC. RANKL and RANK expression was observed in metastatic RCCs in the bone and other organs, suggesting that they play a role in metastasis to the bone and other organs. Recombinant RANKL protein stimulated migration of a clear cell RCC cell line, Caki‐1, in vitro, and this enhanced migration was inhibited by the administration of recombinant OPG protein. Furthermore, multivariate Cox analysis revealed that elevated RANKL and RANK expression with low‐OPG expression was a significant and independent predictor of recurrence, bone metastasis and a poor prognosis. These data suggest that the RANKL–RANK–OPG system is involved not only in the bone metastasis of RCCs but also in metastasis to other organs through the stimulation of cancer cell migration. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.