bluuebunny/crossref_metadata_2025 huggingface dataset:
Nicotinic receptor mechanism in supramammillary nucleus mediates physiological regulation of neural activity in dorsal hippocampal field CA1 of anaesthetized rat
Authors: Ariffin Mohammed Zacky , Jiang Fengli , Low Chian‐Ming , Khanna Sanjay
Published: August 2009

Evidence suggests that stimulation of the region of the rostral pontine oralis (RPO) nucleus and the peripheral application of a noxious stimulus activates an ascending system that also modulates hippocampal neural responses during behavioral arousal. Indeed, the two stimuli and behavioral arousal elicit theta activation and the suppression of population spikes (PS) in dorsal hippocampus field CA1. Interestingly, such neural responses in CA1 are also elicited by microinjection of the cholinergic agonist carbachol into the hypothalamic supramammillary nucleus (SuM). In the present in vivo electrophysiological study, we tested the hypothesis that cholinergic neural elements in the SuM modulate the neural drive to CA1 on RPO stimulation or the peripheral application of a noxious stimulus. Pharmacological investigation showed that intra‐SuM microinjection of either a muscarinic or a nicotinic receptor antagonist attenuated the SuM carbachol‐induced neural effects in CA1, namely, theta activation and PS suppression. However, neither antagonist attenuated the CA1 effects of intra‐SuM microinjection of the excitatory neurotransmitter glutamate. Subsequent investigations revealed that microinjection of only the nicotinic antagonist, mecamylamine, into the lateral SuM selectively attenuated the responses elicited in CA1 by stimulation of the RPO or on nociceptive stimulation with hind paw injection of formalin (5%, 0.05 ml); whereas, microinjection of mecamylamine into the medial SuM did not affect the hippocampal responses elicited by either type of stimulation. Furthermore, application of mecamylamine into the lateral SuM attenuated the CA1 responses induced by injection of formalin into the contralateral, but not the ipsilateral hind paw. The lateralization of drug effect is consistent with the predominant unilateral anatomical connections between the SuM and the septohippocampal region. These findings provide novel evidence that nicotinic cholinoceptive neurons in the lateral SuM are common elements of the neural drive(s) to the hippocampus on RPO activation and noxious stimulation. © 2009 Wiley‐Liss, Inc.
Factors controlling groundwater chemistry in an agricultural area with complex topographic and land use patterns in mid‐western South Korea
Authors: Koh Dong‐Chan , Kim Eun‐Young , Ryu Jong‐Sik , Ko Kyung‐Seok
Published: August 2009

Shallow and bedrock groundwater from granitic aquifers were investigated for the hydrogeochemistry of major and minor constituents in an agricultural area. Nitrate concentrations were observed up to 49 mg/l as NO3‐N, with 22% of samples exceeding the drinking water standard, which could pose a significant threat because most residents rely on groundwater as their drinking water source. Principal component analysis revealed three principal components (PCs): (1) nitrate contamination, contributed by major cations, Cl−, SO$_{4}^{2-}$ and NO$_{3}^{-}$, (2) reduction processes positively involving Fe, Mn and B, and negatively involving dissolved oxygen and NO$_{3}^{-}$ and (3) natural mineralization, involving HCO$_{3}^{-}$ and F−. Cluster analysis, performed on the PC scores, resulted in seven sample groups, which were successfully identified by total depth, elevation and land use. The nitrate‐contaminated groups had mixed land uses, with locally concentrated residential areas. Uncontaminated groundwater groups were found in the natural environment, including high‐altitude spring water and bedrock groundwater with a higher degree of natural mineralization. Shallow groundwater groups in paddy fields in lowlands were affected by reducing environments, of which one group was characterized by high Fe, Mn and B, and negligible nitrate. Groundwater with intermediate nitrate and lower Cl− and SO$_{4}^{2-}$ was found primarily in hilly terrains with orchards and vegetable gardens, indicating lower contaminant loadings than lowland areas. Higher concentrations of F− and nitrate were observed in the nitrate‐contaminated water, which seemed unlikely to be explained by groundwater mixing. The strong acidity generated from nitrification may infiltrate deeper into the aquifer, induce accelerated weathering of bedrock and result in the coexistence of F− and nitrate, which may be an evidence of intense nitrate loading, leading to soil acidification. Multivariate statistical analysis successfully delineated hydrochemical characteristics of groundwater attained by natural and anthropogenic processes in an agriculturally stressed area with complex topographic land use patterns. Copyright © 2009 John Wiley & Sons, Ltd.
What you match does matter: the effects of data on DSGE estimation
Authors: Guerron‐Quintana Pablo A.
Published: August 2009

This paper explores the effects of using alternative combinations of observables for the estimation of Dynamic Stochastic General Equilibrium (DSGE) models. I find that the estimation of structural parameters describing the Taylor rule and sticky contracts in prices and wages is particularly sensitive to the set of observables. In terms of the model's predictions, the exclusion of some observables may lead to estimated parameters with unexpected outcomes, such as recessions following a positive technology shock. More importantly, two ways to assess different sets of observables are proposed. These measures favor a dataset consisting of seven observables. Copyright © 2009 John Wiley & Sons, Ltd.
Interaction energy and the shift in OH stretch frequency on hydrogen bonding for the H2O → H2O, CH3OH → H2O, and H2O → CH3OH dimers
Authors: Campen Richard Kramer , Kubicki James D.
Published: August 2009

The ability to use calculated OH frequencies to assign experimentally observed peaks in hydrogen bonded systems hinges on the accuracy of the calculation. Here we test the ability of several commonly employed model chemistries—HF, MP2, and several density functionals paired with the 6‐31+G(d) and 6‐311++G(d,p) basis sets—to calculate the interaction energy (De) and shift in OH stretch fundamental frequency on dimerization (δ(ν)) for the H2O → H2O, CH3OH → H2O, and H2O → CH3OH dimers (where for X → Y, X is the hydrogen bond donor and Y the acceptor). We quantify the error in De and δ(ν) by comparison to experiment and high level calculation and, using a simple model, evaluate how error in De propagates to δ(ν). We find that B3LYP and MPWB1K perform best of the density functional methods studied, that their accuracy in calculating δ(ν) is ≈ 30–50 cm−1 and that correcting for error in De does little to heighten agreement between the calculated and experimental δ(ν). Accuracy of calculated δ(ν) is also shown to vary as a function of hydrogen bond donor: while the PBE and TPSS functionals perform best in the calculation of δ(ν) for the CH3OH → H2O dimer their performance is relatively poor in describing H2O → H2O and H2O → CH3OH. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010
Electronic properties for small tin clusters Snn (n ≤ 20) from density functional theory and the convergence toward the solid state
Authors: Assadollahzadeh Behnam , Schäfer Sascha , Schwerdtfeger Peter
Published: August 2009

Global minimum structures of neutral tin clusters with up to 20 atoms obtained recently from genetic algorithm simulations within a density‐functional approach (Schäfer et al., J Phys Chem A 2008, 112, 12312) were used to evaluate the corresponding electronic properties. The evolution of these properties with increasing cluster size is discussed in detail and compared with the lighter silicon and germanium clusters. We also discuss the extrapolation of these properties to the bulk limit. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010
Sonographic findings in a case of tetrasomy 9p associated with increased nuchal translucency and Dandy‐Walker malformation
Authors: Nakamura‐Pereira Marcos , Cima Luciana Carneiro do , Llerena Juan Clinton , Guerra Fernando Antonio Ramos , Peixoto‐Filho Fernando Maia
Published: August 2009

We report a case of a 23‐year‐old pregnant woman, who underwent amniocentesis after ultrasound (US) examination in the first trimester which revealed a nuchal translucency thickness of 2.9 mm. Cytogenetic analysis revealed complete tetrasomy of the short arm of chromosome 9. Further US evaluation in the second trimester revealed Dandy‐Walker malformation, ventriculomegaly, bilateral clubfoot, lip and palate clefts, arthrogryposis and hyperechoic kidneys with bilateral pelvic dilatation. At 30 weeks of gestation, a placental abruption was noted and a Cesarean section was performed. The infant died shortly after birth. A review of previous cases of tetrasomy 9p shows that the remarkable sonographic findings are ventriculomegaly, intrauterine growth restriction, genitourinary anomaly, Dandy‐Walker malformation, cleft lip/palate and limb malformation, but the association of tetrasomy 9p and increased nuchal translucency had not been reported. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2009.
Partial hydatidiform mole in septate uterus
Authors: Taori Kishor , Sharbidre Kedar G. , Bopche Sneha , Kulkarni Bipin , Krishnan Vijay , Disawal Amit
Published: August 2009

Partial mole is a form of gestational trophoblastic disease that may be associated with serious medical complications and occasionally progresses to the second trimester of pregnancy. We present a case report of a partial mole diagnosed at 18 weeks of gestation in a septate uterus with molar placenta in one horn and a dead fetus in the other. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2009
Follicular thyroid adenoma with eggshell calcification presenting as an intensely hypermetabolic lesion on 18F‐FDG PET/CT
Authors: Lee Sang Kwon , Rho Byung Hak
Published: August 2009

We report herein a case of follicular thyroid adenoma with an eggshell calcification presenting as an intensely hypermetabolic lesion on combined 18F‐fluorodeoxyglucose whole‐body PET and CT (18F‐FDG PET/CT) performed for staging work‐up in a 68‐year‐old woman who had undergone distal gastrectomy with Billroth II anastomosis for early gastric carcinoma. The mass was intensely hypermetabolic (SUVmax = 21.3 g/mL) on combined 18F‐FDG PET/CT, hypoechoic with an interrupted eggshell calcification on gray‐scale ultrasonography (US), and showed intranodular vascularity on power Doppler US. Follicular adenoma should be considered in the differential diagnosis of a mass with an eggshell calcification on US and intense hypermetabolism on 18F‐FDG PET/CT. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2010
Anatomic variations between Japanese and Caucasian populations in the healthy young adult knee joint
Authors: Hovinga Kristen R. , Lerner Amy L.
Published: August 2009

Our objective was to characterize variations in mechanical knee alignment, tibial torsion, tibial width, and ACL laxity measurements between Japanese and Caucasian populations in the healthy, young adult knee joint. Seventy young adult subjects participated in this study, including 23 Japanese and 47 Caucasian subjects. Coronal magnetic resonance images of the hip, knee, and ankle were acquired for analysis. Japanese subjects had a significantly higher (p = 0.04) varus alignment (1.64 ± 0.43° standard error) than Caucasians (0.55 ± 0.33°), while women exhibited a more valgus alignment (0.16 ± 0.52°) than men (0.94 ± 0.42°, p = 0.04). Significant differences were found in tibial torsion and ACL laxity (p < 0.01) between ethnicities, with Japanese exhibiting lower tibial torsion (33.4 ± 10.0°) and higher ACL laxity (7.5 ± 0.4 mm) measurements compared to Caucasians (38.9 ± 9.5° and 5.7 ± 0.3 mm, respectively). Significant differences between genders were found in hip‐knee‐ankle alignment (p = 0.04), tibial width (p < 0.0001), and ACL laxity (p < 0.01) measurements. Measurements were reliable between observers and for repeated positioning. Our study provides new insight into anatomical and geometric differences in the knee joint between Japanese and Caucasians, as well as between females and males. Further consideration of these results may improve development of implants to accommodate for these differences, and understanding of characteristics leading to increased prevalence of knee OA in certain populations. The use of magnetic resonance imaging to obtain these measurements also allows soft tissue structure characterization without exposure to ionizing radiation. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res
Mechanical stimulation alters tissue differentiation and molecular expression during bone healing
Authors: Palomares Kristy T. Salisbury , Gleason Ryan E. , Mason Zachary D. , Cullinane Dennis M. , Einhorn Thomas A. , Gerstenfeld Louis C. , Morgan Elise F.
Published: August 2009

Further understanding of how mechanical cues modulate skeletal tissue differentiation can identify potential means of enhancing repair following injury or disease. Prior studies examined the effects of mechanical loading on osteogenesis, chondrogenesis, and fibrogenesis in an effort to enhance bony union. However, exploring how mechanical stimuli can divert the bone healing process towards formation of other mesenchymal tissues, as an endpoint, may elucidate new avenues for repair and regeneration of tissues such as cartilage and fibrous tissue. This study investigated the use of mechanical stimulation to promote cartilage rather than bone formation within an osteotomy. Our overall goal was to define skeletal tissue distribution and molecular expression patterns induced by the stimulation. Retired breeder Sprague‐Dawley rats (n = 85) underwent production of a mid‐diaphyseal, transverse femoral osteotomy followed by external fixation. Beginning on postoperative day 10 and continuing for 1, 2, or 4 weeks, a cyclic bending motion (+35°/−25° at 1 Hz) was applied in the sagittal plane for 15 min/day for 5 consecutive days/week. Control animals experienced continuous rigid fixation. Histological and molecular analyses indicated that stimulation substantially altered normal bone healing. Stimulated specimens exhibited an increase in cartilage volume over time, while control specimens demonstrated bony bridging. Stimulation induced upregulation of cartilage‐related genes (COL2A1 and COL10A1) and downregulation of bone morphogenetic proteins (BMPs) ‐4, ‐6 and ‐7. However, BMP‐3 was upregulated with stimulation. These findings illustrate that mechanical cues can selectively modulate osteogenesis and chondrogenesis in vivo, and suggest a potential basis for treatment regimens for injured or diseased cartilaginous tissues. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res
Desmoid cell motility is induced in vitro by rhEGF
Authors: Joyner David E. , Trang Sylvia H. , Damron Timothy A. , Aboulafia Albert J. , Cummings Judd E. , Randall R. Lor
Published: August 2009

Desmoid tumors are benign but locally invasive myofibroblastic lesions that arise predominantly in the abdominal wall or shoulder and are prone to aggressive local recurrences. A perceived association between desmoid activity and the expression of growth factors during pregnancy or following trauma suggests a cause‐and‐effect relationship between growth factor stimulation and desmoid invasiveness. We used Boyden Chambers to quantify cell motility in order to determine the effect of growth factor stimulation on desmoid cell migration. Desmoid cell cultures were treated under serum‐free conditions with epidermal growth factor (rhEGF) or transforming growth factor alpha (rhTGFα). Additional cell cultures were pretreated under serum‐free conditions with the EGF receptor (EGFR) inhibitor AG1478, alone or in combination with the TGFβ1 receptor inhibitor SB431542, and then stimulated with growth factor prior to being assayed for cell motility. The experiments demonstrated a direct dose‐dependent relationship between rhEGF stimulation and desmoid motility. In contrast, rhTGFα was less effective at inducing cell migration. rhEGF‐induced cell migration could be diminished, but not reduced to control levels, by inhibiting EGFR. When EGF and TGFβ1 receptors were inhibited simultaneously, the level of rhEGF‐induced cell migration was reduced significantly beyond the level of cell migration generated by inhibition of EGFR alone. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res
Improved quality assessment of proprietary Chinese medicines based on multi‐chemical class fingerprinting
Authors: Chen Dan , Zhao Sandy Shuo , Leung Kelvin Sze‐Yin
Published: August 2009

Our present study constitutes the first successful attempt to employ eight distinctive chemical groups of compounds for the quality evaluation of a complex traditional Chinese herbal medicine (TCHM) material: BaZhen YiMu (BZYM). Due to the complexity of its matrix, which is composed of nine different herbal ingredients, five representative chemical groups encompassing representative bioactive markers were initially chosen as targets for the quality assessment of this preparation. Furthermore, with the aid of LC‐ESI‐MS, three additional chemical groups were characterized. In summary, a total of nineteen markers belonging to eight different chemical groups were selectively displayed in the chromatographic fingerprint of BZYM preparation. With this fingerprint, the overall quality of any BZYM preparation can be comprehensively authenticated. The chromatographic separation was performed on an HP C18 AQ column with a gradient elution of ACN and aqueous solution containing 0.1% phosphoric acid at the optimal detection wavelength of 230 nm. The established method was rigorously validated with respect to the ICH guidelines and represents the most extensive and facile HPLC quality control technique for this formulation. Compared with the conventional method of using a single or only a few markers of the same chemical group, this technique provides a new dimension for TCHM quality control.
Curcumin: A potential radio‐enhancer in head and neck cancer
Authors: Khafif Avi , Lev‐Ari Shahar , Vexler Akiva , Barnea Itai , Starr Alex , Karaush Vicki , Haif Sasha , Ben‐Yosef Rami
Published: August 2009

Objectives/Hypothesis:

To investigate whether curcumin enhances the cytotoxic effect of radiotherapy in head and neck squamous cell carcinoma (HNSCC).

Methods:

HNSCC cell lines SCC‐1, SCC‐9, KB, as well as A431 cell line were treated with curcumin, irradiation, or their combination. Cell viability was evaluated by XTT assay. Cyclooxygenase‐2 (COX‐2), epithelial growth factor receptor (EGFR), and p‐Erk1/2 were measured by Western blot analysis. CD‐1 athymic nude mice with orthotopic implanted SCC‐1 cells, were treated with control diet, curcumin containing diet, local single‐dose radiation, or combination.

Results:

Curcumin (IC50 range, 15–22 μM) and radiation inhibited cell viability in all cell lines were tested. The combination of curcumin and radiation resulted in additive effect. Curcumin decreased COX‐2 expression and inhibited phosphorylation of EGFR in SCC‐1 cells. In tumor‐bearing mice the combination regimen showed a decrease in both tumor weight (25%, P = .09) and tumor size (15%, P = .23) compared to the nontreated mice.

Conclusions:

Curcumin inhibited HNSCC cell growth and augmented the effect of radiation in vitro and in vivo. A possible mechanism is inhibition of COX‐2 expression and EGFR phosphorylation. Laryngoscope, 2009
Survival impact of treatment options for papillary microcarcinoma of the thyroid
Authors: Lin Harrison W. , Bhattacharyya Neil
Published: August 2009

Objectives/Hypothesis:

Evaluate the impact of medical and surgical interventions on the survival of patients with papillary microcarcinoma (PMC) of the thyroid, a common tumor with an increasing worldwide incidence.

Study Design:

Cross‐sectional population analysis of a prospectively maintained database.

Methods:

Cases of nonmetastatic PMC treated with cancer‐directed surgery with or without postoperative radioactive iodine (RAI) therapy were extracted from the Surveillance, Epidemiology and End Results Database (1988–2005). Kaplan‐Meier disease‐specific survival (DSS) and overall survivals were compared according to extent of thyroidectomy and use of RAI therapy. Cox regression analysis was performed to determine the influence of these factors on survival.

Results:

A total of 7,818 cases of PMC were identified. Overall actuarial survival rates at 10 and 15 years were 96.6% and 96.3%, respectively. DSS was 99.9% at both time intervals, with a total of 10 thyroid cancer‐related deaths. There were no significant differences in DSS for patients who underwent total thyroidectomy, near‐total/subtotal thyroidectomy, or lobectomy (P = .239). DSS for patients receiving RAI therapy was not significantly different than that of patients who did not (P = .504). On multivariate analysis, only increasing age at diagnosis, successfully predicted poor DSS (P = .001), whereas gender (P = .481), use of RAI therapy (P = .633), and extent of thyroidectomy (P = .104) did not.

Conclusions:

PMC carries an excellent prognosis with respect to both overall and disease‐specific survival that is independent of surgical extent and the use of RAI therapy. An isolated, fine‐needle–aspiration proven unilateral PMC focus in a patient lacking evidence of metastatic disease may be treated with lobectomy alone. Laryngoscope, 2009
Functional Polymers for Targeted Delivery of Nucleic Acid Drugs
Authors: Mok Hyejung , Park Tae Gwan
Published: August 2009

Cationic polymers have been chemically modified with a variety of targeting molecules such as peptides, proteins, antibodies, sugars and vitamins for targeted delivery of nucleic acid drugs to specific cells. Stimuli‐sensitive polymers exhibiting different size, charge and conformation in response to physiological signals from specific cells have also been utilized for targeted delivery. To achieve target‐specific delivery of nucleic acids, conjugation chemistry is critical to produce stable nanosized polyplexes tethered with cell‐recognizable ligands for facile cellular uptake via a receptor‐mediated endocytic pathway. In this review, synthetic strategies of functional cationic polymers with various targeting ligands are presented.

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Inhibition of copper corrosion by modifying cysteine self‐assembled film with alkylamine/alkylacid compounds
Authors: Zhang D.‐Q. , Gao L.‐X. , Cai Q.‐R. , Lee K. Y.
Published: August 2009

Complex self‐assembled monolayers (SAMs) were prepared by modifying the adsorption of cysteine with dodecylacid (DAC) and with dodecylamine (DAM) on copper surfaces. Their protective effects against copper corrosion were investigated by potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS) in 0.5 M HCl aqueous solution. Results show that SAMs suppress cathodic current densities and shift the corrosion potential toward more negative values. Two types of complex SAMs enhance the anticorrosion effect of cysteine SAMs. PM3 semi‐empirical quantum calculations were used to obtain the quantum chemical parameters. The complex SAMs formed from cysteine and DAM have the higher EHOMO level and the better protection effect.
Study on the effect of corrosion on the tensile behavior of an AZ91 alloy
Authors: Wang Q. , Liu Y. H. , Zhang L. N. , Song Y. L. , Zhang D. W. , Li C. F.
Published: August 2009

The effect of corrosion on the tensile behavior of an as‐cast AZ91 alloy was investigated via systematical experiments. The corrosion residual strength of the AZ91 magnesium alloy is approximately negative linear dependent on the extreme depth of corrosion pit, which was quantitatively obtained by the corrosion morphology analysis and the statistic analysis. Experimental results reveal that the corrosion residual strength of the AZ91 magnesium alloy dropped quickly in the first 40 h due to the initiation and development of the corrosion pit and subsequently decreased slowly as a result of the development of the corrosion pit encountered the β phase. The β phase at the grain boundary of the primary α phase acts as an effective barrier to prevent the development of the corrosion pit into the alloy matrix and thus remarkably prevents the drop of the corrosion residual strength. In general, the variation of the corrosion residual strength exhibits an exponential decay regulation within the testing time. Consequently, the empirical prediction of the corrosion residual strength was given with regard to the variation of the corrosion residual strength varied with the immersion time.
Evaluation of the uniform current density assumption in cathodic protection systems with close anode‐to‐cathode arrangement
Authors: Martinez S.
Published: August 2009

Cathodic protection modelling often involves making assumptions about geometric features and material characteristics that directly impact accuracy of solutions. In the present paper, predictive power of the model using approximate uniform current boundary condition on the cathode is validated against the model using nonlinear cathode polarization curves representative of low‐carbon steel structure of common geometry, buried in soil or immersed in seawater. In order to explore the worst case scenario, the present example deals with a large diameter pipeline (Ø 1.2 m) and a wire anode (Ø 0.05 m), separated by a distance d, both embedded in an infinite space of conductivity κ. The calculation is performed for the two sets of parameters – κ and limiting current density of oxygen reduction, il. For simulation of CP systems in seawater κ = 4.79 S/m and il = −86 µA/cm2 and for CP system in soil, κ = 10−3 S/m and il = −1.1 µA/cm2. The other physical parameters were identical for both systems (Tafel slopes ba = 60 mV/dec, bc = 120 mV/dec and equilibrium potentials $\phi _{\rm e}^{\rm a} = - 700\,{\rm mV}$, $\phi _{\rm c}^{\rm a} = - 800\,{\rm mV}$). The results were visualized to best exemplify the general trends in potential and current distributions that appear upon switch between uniform and nonlinear cathodic boundary conditions.
Response Characteristics of Thermoresponsive Polymers Using Nanomechanical Cantilever Sensors
Authors: Bradley Calvin , Jalili Nader , Nett Sebastian K. , Chu Liqiang , Förch Renate , Gutmann Jochen S. , Berger Rüdiger
Published: August 2009

We investigated coatings of thermally responsive thin polymer films prepared on nanomechanical cantilever sensor (NCS): (i) a PNIPAM brush, and (ii) an interlinked ppDEA polymer. Upon heating from 22 to 50 °C in water, a minimum in the differential deflection between 31.9 ± 1.7 °C (PNIPAM) and 47.7 ± 1.9 °C (ppDEA) was measured. The minimum in differential deflection can be associated with the lower critical solution temperature (LCST) of the films. Below the LCST the NCS deflection corresponds to a bending toward the thermally responsive polymer film side, associated to dehydration. At higher temperature, the deflection was reversed, i.e., away from the polymer coating. This response is mainly attributed to a bimaterial effect between the collapsed polymer and the NCS material. The LCST of the PNIPAM brush layer and the ppDEA film were close to that reported for the bulk polymers.

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Hop bitter acids efficiently block inflammation independent of GRα, PPARα, or PPARγ
Authors: Van Cleemput Marjan , Heyerick Arne , Libert Claude , Swerts Katrien , Philippé Jan , De Keukeleire Denis , Haegeman Guy , De Bosscher Karolien
Published: August 2009

Hop (Humulus lupulusL.) is an essential ingredient of beer, where it provides the typical bitter taste, but is also applied in traditional folk medicine for sedative and antibacterial purposes. In this study, we demonstrate and compare the anti‐inflammatory effect of various classes of hop bitter acids (HBA), including α‐acids (AA), β‐acids (BA), and iso‐α‐acids (IAA), in fibroblasts, which are important players in the inflammatory response. All three studied classes of HBA blocked the tumor necrosis factor alpha (TNF)‐induced production of the cytokine IL6, and inhibited the transactivation of the pro‐inflammatory transcription factors nuclear factor kappa B (NF‐κB), activator protein‐1 (AP‐1), and cAMP‐response element‐binding protein (CREB). In this respect, the six‐membered ring compounds AA and BA showed equal potency, whereas the five‐membered ring compounds, IAA, were effective only when used at higher concentrations. Furthermore, with regard to the mechanism of NF‐κB suppression, we excluded a possible role for glucocorticoid receptor alpha (GRα), peroxisome proliferators‐activated receptor alpha/gamma (PPARα or PPARγ), nuclear receptors (NRs) that are also known to inhibit inflammation by directly interfering with the activity of pro‐inflammatory transcription factors. Interestingly, combining hop acids and selective agonists for GRα, PPARα, or PPARγ resulted in additive inhibition of NF‐κB activity after TNF treatment, which may open up new avenues for combinatorial anti‐inflammatory strategies with fewer side effects. Finally, systemic administration of HBA efficiently inhibited acute local inflammationin vivo.
The usefulness of 2D DOSY and 3D DOSY‐COSY 1H NMR for mixture analysis: application to genuine and fake formulations of sildenafil (Viagra)
Authors: Trefi Saleh , Gilard Véronique , Balayssac Stéphane , Malet‐Martino Myriam , Martino Robert
Published: August 2009

Two‐dimensional diffusion ordered spectroscopy (DOSY) 1H NMR is proposed to analyze drugs that are complex mixtures in order to discriminate genuine from fake formulations. The method was applied to the analysis of 17 formulations of sildenafil, one being genuine Viagra and the others illegally manufactured formulations of this drug coming from India, Syria and China. It enabled (i) distinguishing imitations or counterfeit from the authentic formulation, (ii) detecting the presence of sildenafil or adulterants, (iii) gaining information on the formulation process by detection of various excipients, thus giving a precise and global ‘signature’ of the manufacturer. Even though some samples are slightly overdosed, the quality of products manufactured in India and Syria was better than that of Chinese formulations which were adulterated with vardenafil and homosildenafil. This study also presents a three‐dimensional DOSY‐COSY 1H NMR experiment that provides both virtual separation and structural information. Copyright © 2009 John Wiley & Sons, Ltd.
Characterization of the complex formation of 1,6‐anhydro‐β‐maltotriose with potassium using 1H and 39K NMR spectroscopy
Authors: Kato Takayuki , Tsubono Koji , Kamo Osamu , Kato Toshiyo , Furihata Kazuo , Fujimoto Takashi , Machinami Tomoya , Tashiro Mitsuru
Published: August 2009

The 1H and 39K longitudinal relaxation times (T1) and 1H diffusion coefficients were measured to investigate the complex formation of 1,6‐anhydro‐β‐maltotriose and potassium ions. Although the 1H‐T1 values of H3′, H5′, H1″ and H4″ decreased in the presence of potassium ions, 1H chemical shifts and 1H diffusion coefficients did not show significant changes. The long‐range coupling constants of 3JC−H around the glycosyl bonds did not show significant changes either. In the measurements of 39K spectra, the 39K signal obviously broadened and the 39K‐T1 values decreased in the presence of 1,6‐anhydro‐β‐maltotriose, indicating the complex formation of 1,6‐anhydro‐β‐maltotriose and potassium ions. These results indicate that the conformation and molecular volume were unaffected in the complex formation. Copyright © 2009 John Wiley & Sons, Ltd.
Metallocene‐Catalyzed Gas‐Phase Ethylene Copolymerization: Kinetics and Polymer Properties
Authors: Bergstra Michiel F. , Weickert Günter , Meier Gerben B.
Published: August 2009

The influence of 1‐hexene is examined on the kinetics of ethylene copolymerization with a metallocene catalyst in gas phase. A model is derived, which is able to describe a large reaction rate increase due to a small amount of incorporated comonomer. This complexation model describes the measured reaction rates for ethylene and 1‐hexene, and the co‐monomer incorporation. Polymer properties were analyzed, such as comonomer weight fraction. The density, melting point, and molecular weight of the produced polymer decreased with increase in 1‐hexene gas concentration. The in situ 1‐hexene sorption is estimated and follows Henry's law, but seems much higher than reported in the literature.

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Miniemulsion Copolymerization of Ethylene and Vinyl Acetate
Authors: Guo Juchen , Choi Kyu Yong , Schork F. Joseph
Published: August 2009

The copolymerizations of a gaseous monomer (ethylene) and a liquid monomer (vinyl acetate) via emulsion and miniemulsion polymerizations are reported. Reactions in which the vinyl acetate was introduced in both batch and semibatch modes are carried out. (Ethylene introduction is always in a semibatch model since the polymerization is carried out under a constant pressure of ethylene in the reactor headspace.) The results are compared, drawing the conclusion that miniemulsion copolymerization has an advantage over conventional emulsion polymerization for monomers with very low water solubility (including gaseous monomers) due to their nucleation in monomer droplets without transport through the aqueous phase.

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Application of Exp‐function method to EW‐Burgers equation
Authors: Biazar J. , Ayati Z.
Published: August 2009

In this article, Exp‐function method is used to obtain an exact solution of the equal‐width wave‐Burgers equation (EW‐Burgers). The method is straightforward and concise, and its applications are promising. It is shown that Exp‐function method, with the help of symbolic computation, provides a very effective and powerful mathematical tool for solving EW‐Burgers equation. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2010
New (PP/EPR)/nano‐CaCO3 based formulations in the perspective of polymer recycling. Effect of nanoparticles properties and compatibilizers
Authors: Mnif Nizar , Massardier Valérie , Kallel Tasnim , Elleuch Boubaker
Published: August 2009

Phase structure of composite polypropylene (PP)/ethylene–propylene–rubber (EPR)/coated nano‐CaCO3 composites, used in the manufacture of bumpers, with and without compatibilizers has been investigated using scanning electron microscopy (SEM), dynamic mechanical analysis (DMA) mechanical tests, and differential scanning calorimetry (DSC). Blends of various compositions were prepared using a corotating twin‐screw extruder. The experimental results indicated that the dispersion of nanoparticles in (PP/EPR) depends on their surface (stearic acid and fatty acid coatings). In both cases, the final morphology is the core–shell structure in which EPR acts as the shell part encapsulating coated nano‐CaCO3. In this case, EPR‐g‐MAH copolymer does not improve the interface between (PP/EPR) and nanoparticles but PEP propylene ethylene copolymer should be preferentially localized at the interface of PP and (EPR/nano‐CaCO3) phases generating an improved adherence, which will ensure a better cohesion of the whole material. According to the nature of the compatibilizers and surface treatment, it is believed that the synergistic effect of both the EPR elastomer and CaCO3 nanoparticles should account for the balanced performance of the ternary composites. Copyright © 2009 John Wiley & Sons, Ltd.
Identification of a novel 12p13.3 amplicon in nasopharyngeal carcinoma
Authors: Or Yvonne Y‐Y , Chung Grace T‐Y , To Ka‐Fai , Chow Chit , Choy Kwong‐Wai , Tong Carol Y‐K , Leung Alice W‐C , Hui Angela B‐Y , Tsao Sai‐Wah , Ng Ho‐Keung , Yip Timothy T‐C , Busson Pierre , Lo Kwok‐Wai
Published: August 2009

Nasopharyngeal carcinoma (NPC) is a distinct type of head and neck cancer commonly occurring in southern China. To decipher the molecular basis of this cancer, we performed high‐resolution array CGH analysis on eight tumour lines and 10 primary tumours to identify the genes involved in NPC tumorigenesis. In this study, multiple regions of gain were consistently found at 1q21‐q24, 7q11‐12, 7q21‐22., 11q13, 12p13, 12q13, 19p13 and 19q13. Importantly, a 2.1 Mb region at 12p13.31 was highly amplified in a NPC xenograft, xeno‐2117. By FISH mapping, we have further delineated the amplicon to a 1.24 region flanked by RP11‐319E16 and RP11‐433J6. Copy number gains of this amplicon were confirmed in 21/41 (51%) primary tumours, while three cases (7.3%) showed high copy number amplification. Among the 13 genes within this amplicon, three candidate genes, lymphotoxin beta receptor (LTβR), tumour necrosis factor receptor superfamily memeber 1A (TNFRSF1R) and FLJ10665, were specifically over‐expressed in the NPC xenograft with 12p13.3 amplification. However, only LTβR was frequently over‐expressed in primary tumours. LTβR is a member of the TNF family of receptors, which can modulate NF‐κB signalling pathways. Over‐expression of LTβR in nasopharyngeal epithelial cells resulted in an increase of NF‐κB activity and cell proliferation. In vivo study showed that suppression of LTβR by siRNA led to growth inhibition in the NPC tumour with 12p13.3 amplification. These findings implied that LTβR is a potential NPC‐associated oncogene within the 12p13.3 amplicon and that its alteration is important in NPC tumorigenesis. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Effect of loading‐unloading cycles on impact‐damaged jute/glass hybrid laminates
Authors: De Rosa Igor Maria , Santulli Carlo , Sarasini Fabrizio , Valente Marco
Published: August 2009

The production of glass/plant fiber hybrid laminates is a possibility for obtaining semistructural materials with sufficient impact properties, and a better life cycle analysis (LCA) profile than fiberglass. The simplest and possibly the most effective configuration for the production of these hybrids would involve the use of a plant fiber reinforced laminate as the core between two glass fiber reinforced laminates. A main limitation to the use of composites including plant fibers is that their properties may be significantly affected by the presence of damage, so that even the application of a low stress level can result in laminate failure. In particular, it is suggested that when loading is repeatedly applied and removed, residual properties may vary in an unpredictable way. In this work, E‐glass/jute hybrid reinforced laminates, impacted in a range of energies (10, 12.5, and 15 J), have been subjected to post‐impact cyclic flexural tests with a step loading procedure. This would allow evaluating the effect of damage dissipation offered by the plant fiber reinforced core. The tests have also been monitored by acoustic emission (AE), which has confirmed the existence of severe limitations to the use of this hybrid material when impacted at energies close to penetration. POLYM. COMPOS., 2009. © 2009 Society of Plastics Engineers
Crystalline transition behavior of sisal in cycle process
Authors: Yi Changhai , Tian Lei , Tang Fen , Wang Luoxin , Zou Hantao , Xu Weilin
Published: August 2009

In this study, the effects of cycle process on crystalline transition behavior of sisal fiber were investigated in various conditions (in air, in composites and in argon) by XRD analysis. The results indicated that the sisal cellulose falls into cellulose I, and the polymorphic transformation didn't occur for sisal cellulose after cycle process. With increasing of thermal cycle times, the crystalline size of sisal became smaller gradually, but the change was not obvious when sisal fiber was treated thermally in air and in argon before five times. The change trend of crystalline index of sisal after cycle process in air and in argon was similar. However, it is different in composites. From once to 10 times cycle process, the crystalline index of sisal fiber was degressive. When the cycle times was close to 15, crystalline index increased gradually. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
On the prediction of long‐term creep‐failure of GRP pipes in aqueous environment
Authors: Guedes Rui Miranda , Sá Alcides , Faria Hugo
Published: August 2009

The aim of this work was to study the long‐term failure of GRP (Glass fiber‐reinforced Polymer) pipes under the influence of moisture absorption. These pipes are used in water transportation, which has an important effect on the mechanical properties of the polymeric matrix. The GRP pipes are usually tested under ring deflection or internal pressure conditions. This study presents and analyzes experimental creep‐rupture data obtained from standard test methods under ring deflection conditions. This loading configuration simulates in laboratory the conditions verified in a subsoil installation. The creep testing was carried out under constant dead weight on unconditioned and preconditioned samples in a submerged condition. The diametrical deflection of samples was measured periodically, and the time to failure of each sample was recorded. The main purpose of this work was to determine the short and long‐term rupture energies of GRP pipes and assess the influence of moisture preconditioning on those values. The observed failure mode was always the same. It was concluded that the energy at failure decreases with time. The influence of the preconditioning on the creep‐rupture of GRP pipes was considered negligible. Different time‐dependent failure models were described and used for long‐term extrapolation of the experimental data. The maximum strain at failure decreased about 12% from 0.1 to 1,000 hr of creep testing. Furthermore, data extrapolation to 50 years predicts a reduction of strength of about 60%, founded on the most conservative time‐dependent failure criterion. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
Primary care, secondary care or both: is there a consensus on long term management of diabetes mellitus?
Authors: Flanagan DE , Craig A , English PJ
Published: August 2009

The aim of this study was to test the hypothesis that specific referral guidelines are unhelpful because of wide variations in individual clinical practice.

A series of representative diabetes case studies were given to a group of primary care, general practice (GP) clinicians for comment. The same cases were given to a group of secondary care clinicians. The suggested management strategies were compared.

Overall the results show very little agreement among either primary care or secondary care clinicians for a series of commonly presenting clinical cases. Approximately a third of GP responses for each group of cases suggested primary care management with a third each split between secondary or shared care. Long term follow up of the cases was also disputed but a greater proportion felt that continuing specialist input would not be required. Patient choice was not considered an important factor in deciding the most appropriate place for care.

Although specific management strategies would be helpful for service planners, in reality clinicians differ greatly in what they feel should be managed in primary or secondary care. This variability needs to be considered in future planning for long term conditions such as diabetes. Copyright © 2009 John Wiley & Sons, Ltd.
Glibenclamide controls ketosis‐prone diabetes in a 38‐year‐old woman with Kir6.2 mutation
Authors: Jose B , Griffiths U , Barrett PhD T , Hattersley AT , Milles JJ
Published: August 2009

Monogenic forms of diabetes, where there is a single gene defect causing diabetes, are rare, accounting for about 1‐2% of all cases of diabetes in young people. Neonatal diabetes is one form of monogenic diabetes. It usually presents within six months of birth and can be permanent or transient. Several mutations in the KCNJ11 gene lead to permanent neonatal diabetes by interfering with insulin release from islet cells. These patients can be treated with sulphonylureas as they facilitate insulin secretion by acting on the mutated pancreatic potassium channel.

We report the case of a patient with KCNJ11 S3C mutation, who is the oldest patient with neonatal diabetes to have successfully transferred from insulin to sulphonylureas. She was diagnosed with diabetes at the age of four and was treated as having type 1 diabetes mellitus. Her glycaemic control was always sub‐optimal; she had had several admissions with diabetic ketoacidosis. Her daughter who developed diabetes at six weeks was found to have neonatal diabetes, which led to her genetic testing. Our patient was also diagnosed with the same KCNJ11 mutation as her daughter. At 38 years of age, after outpatient assessment, she was started on glibenclamide and in three weeks came off insulin completely, achieving good glycaemic control with glibenclamide. Her HbA1c improved from 10% pre‐transfer to 5.9% in four months. Copyright © 2009 John Wiley & Sons, Ltd.
Foaming behavior of high‐melt strength polypropylene/clay nanocomposites
Authors: Bhattacharya Subhendu , Gupta Rahul K. , Jollands Margaret , Bhattacharya Sati N.
Published: August 2009

The foaming behavior of high‐melt strength polypropylene (HMS‐PP) and HMS‐PP/Cloisite 20A nanocomposites (PPNC) was studied in a batch process. PPNCs with 2, 4, 8, and 10 wt% clay were prepared in a twin screw extruder. The morphology of the nanocomposites was studied using XRD and TEM. Subsequently, foaming experiments were conducted using supercritical CO2 as the blowing agent in a batch process, and foams with cell sizes varying from the sub micrometer to the micro meter range were prepared. The effect of variation in saturation pressure and temperature, foaming temperature, foaming time, and quench temperature was determined experimentally. Dynamic rheological measurements were conducted to relate the influence of nanocomposites morphology with foam cell growth and nucleation. Extensional rheological measurements were also conducted to detect the presence of strain hardening effect at the foaming temperatures used in the experiment. It was found that the nucleation efficiency of clay reduces with increase in clay loading. Also, the optimum amount of filler for generation of fine celled foams was found to be around the percolation threshold of the polymer. The extended strain hardening effect shown by the polymer in presence of clay plays an important role in stabilizing foam cell sizes. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Oriented and low‐density tin dioxide film by sol–gel mineralizing tin‐contained hydroxypropyl cellulose lyotropic liquid crystal for laser‐induced extreme ultraviolet emission
Authors: Nagai Keiji , Gu Qincui , Yasuda Yuzuri , Norimatsu Takayoshi , Fujioka Shinsuke , Nishimura Hiroaki , Miyanaga Noriaki , Izawa Yasukazu , Mima Kunioki
Published: August 2009

A series of tin‐doped hydroxypropyl cellulose (HPC) lyotropic liquid crystal (LC) was synthesized using a simple process and their properties were characterized using selective reflection, wide‐angle X‐ray diffraction (WAXD), and the band texture observed under polarized optical microscope. The present preparation is applicable for mass production using large substrate with low cost HPC. A cholesteric lyotropic LC phase was observed for the hybrid solution with higher than 40 wt % HPC. After sol–gel condensation, the HPC‐Sn hybrid LC films were calcined at 400 °C and the as‐prepared product was determined to obtain tin dioxide (SnO2) which was characterized using WAXD. The iridescent color and ∼2 nm structure seen after the condensation disappeared in the as‐prepared SnO2. Scanning electronic microscope images of the SnO2 showed that the HPC content in the HPC‐Sn hybrid played an important role in controlling the SnO2 morphology. A spectrum of relatively monochromatic extreme ultraviolet (13.5 nm) emission was measured in the as‐prepared SnO2 in comparison with bulk tin and inverse opal SnO2. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4566–4576, 2009