bluuebunny/crossref_metadata_2025_split huggingface dataset:
NMR Investigation of the Bound Conformation of Natural and Synthetic Oligomannosides to Banana Lectin
Authors: Clavel Caroline , Canales Angeles , Gupta Garima , Cañada F. Javier , Penadés Soledad , Surolia Avadhesha , Jiménez‐Barbero Jesús 
Published: February 2007

AbstractThe conformational behaviour of three mannose‐containing oligosaccharides, namely, the α1→3[α1→6] trisaccharide, a heptasaccharide with α1→2, α1→3 and α1→6 linkages and a tetrasaccharide consisting of α1→3 and α1→2 linkages, when bound to banana lectin (BanLec) has been evaluated by trNOE NMR methods and docking calculations. It was found that the molecular recognition event involves a conformational selection process with only one of the conformations present in the free state of the sugar being recognised at the lectin binding site. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Stereoselective Intramolecular Oxazine Formation by a π‐Allylpalladium Complex Catalyzed by Pd0
Authors: Joo Jae‐Eun , Lee Kee‐Young , Pham Van‐Thoai , Ham Won‐Hun 
Published: February 2007

AbstractAn efficient procedure for synthesizing oxazines was developed by the palladium(0)‐catalyzed intramolecular cyclization of a benzamide through a π‐allylpalladium(II) complex. Unlike other palladium‐catalyzed reactions, the temperature was found to be a key factor in determining the stereochemistry of the oxazine. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
A Pronounced Anionic Effect in the Pd‐Catalyzed Buchwald–Hartwig Amination Reaction Revealed in Phosphonium Salt Ionic Liquids
Authors: McNulty James , Cheekoori Sreedhar , Bender Timothy P. , Coggan Jennifer A. 
Published: February 2007

AbstractThe Pd‐mediated Buchwald–Hartwig amination reaction of aryl halides in a phosphonium salt ionic liquid consisting of a trihexyl(tetradecyl)phosphonium cation with a range of anions has been investigated. A pronounced anionic effect was uncovered with the reaction proceeding readily with weakly nucleophilic diarylamines only in the presence of noncoordinating anions. A mechanism is postulated to explain these results and it involves a rate‐limiting ligand exchange step that proceeds through a dissociative pathway.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Low Potential Detection of NADH at Titanium‐Containing MCM‐41 Modified Glassy Carbon Electrode
Authors: Dai Zhihui , Lu Guofei , Bao Jianchun , Huang Xiaohua , Ju Huangxian 
Published: February 2007

AbstractTitanium‐containing MCM‐41 (Ti‐MCM‐41) modified glassy carbon electrode (GCE) can exhibit an excellent electrocatalytic activity towards the oxidation of β‐Nicotinamide adenine dinucleotide (NADH). A dramatic decrease in the over‐voltage of NADH oxidation reaction is observed at 0.28 V (vs. SCE). The modified electrode is found to be stable and reproducible. The electrode shows a linear response for a wide range of 10–1200 μM NADH and the detection limit is 8.0 μM. Ti‐MCM‐41 mesoporous molecular sieves provide an efficient matrix for development of NADH biosensors and the prepared electrode not only can be used to detect the concentration of NADH in biochemical reaction, but also as the potential matrix of the construction of dehydrogenases biosensor.
Development of Streptavidin Carrying Magnetic Nanoparticles and Their Applications in Electrochemical Nucleic Acid Sensor Systems
Authors: Erdem Arzum , Sayar Filiz , Karadeniz Hakan , Guven Guldem , Ozsoz Mehmet , Piskin Erhan 
Published: February 2007

AbstractThe aim of this study is to investigate the applicability of streptavidin carrying magnetic nanoparticles in electrochemical nucleic acid sensor systems. The magnetite (Fe3O4) nanoparticles were prepared by co‐precipitation technique, and then they were coated with a carboxylic acid containing polymer layer. Streptavidin molecules were immobilized onto the surfaces of these magnetic nanoparticles (with two different average diameter of 125 and 225 nm) via these functional groups. An electrochemical nucleic acid sensor system composed of a disposable graphite sensor, pencil graphite electrode (PGE) and differential pulse voltammetry (DPV) was used for measurement of guanine oxidation signal observed at +1.0 V. In the hybridization tests biotinylated inosine substituted probe was immobilized onto the magnetic nanoparticles and hybridization with its complementary target at the surface of particles within the medium was exhibited successfully by using this electrochemical sensor system. For electrochemical detection of sequence specific DNA hybridization and its selectivity studies, the biotinylated hepatitis B Virus (HBV) wild type probe was immobilized onto the nanoparticles. The guanine oxidation signals were measured in the solutions containing no target, the complementary target, a single‐base mismatch target, and noncomplementary target oligonucleotides. A significant guanine oxidation signal (71 nA) was observed with the complementary target due to complete hybridization, while with single‐base mismatch target, the signal at the same conditions was quite low about 14 nA. However, in the case of the noncomplementary target, there was a low but observable mean signal about 9 nA (showing the nonspecific interaction). The detection limit (S/N=3) was found as 43.11 pmol/mL target concentration obtained in 20 min hybridization time.
GABAB receptor blockade enhances theta and gamma rhythms in the hippocampus of behaving rats
Authors: Leung L. Stan , Shen Bixia 
Published: February 2007

AbstractThe participation of GABAB receptors in hippocampal EEG generation was studied by intracerebroventricular (icv) and intracerebral infusions of GABAB receptor antagonist p‐(3‐aminopropyl)‐p‐diethoxymethyl‐phosphinic acid (CGP35348) in freely behaving rats. During awake‐immobility, icv CGP35348 induced a theta rhythm and increased gamma waves (30–100 Hz) in the hippocampus. The immobility theta peaked at 6–7 Hz and had a theta phase in CA1 stratum radiatum of ∼160° with reference to the theta at the alveus, when compared with ∼130° during walking. Immobility theta power peaks at 6–7 Hz was also found in normal rats, and it was detected in 27% of the EEG segments during immobility. Incidence of immobility theta increased to 87.5% after 480 nmol of CGP35348 icv. Muscarinic antagonist scopolamine (5 mg/kg, ip) suppressed the induction of immobility theta and the gamma power increase after icv CGP35348. CGP35348 icv did not significantly change the hippocampal theta power at 7–8 Hz during walking (theta fundamental), but it increased power at 12–15 Hz, at the second harmonic of theta. CGP35348 icv also increased 30–50 Hz gamma power during walking. Medial septal infusion of CGP35348 (12 nmol in 0.4 μl) increased the power and the frequency of the hippocampal theta second harmonic during walking, but did not increase gamma activity. Infusion of CGP35348 (8 nmol in 0.4 μl) in the hippocampus increased the local gamma activity at 30–100 Hz, but did not induce immobility theta or affect the walking theta rhythm. In conclusion, icv GABAB receptor blockade increased an atropine‐sensitive input that generated an immobility theta rhythm, while GABAB receptor blockade of the medial septum increased atropine‐resistant theta harmonics possibly generated by apical dendritic spikes. GABAB receptor blockade may enhance cognitive task performance by activating hippocampal theta and gamma rhythms in behaving rats. © 2007 Wiley‐Liss, Inc.
Neutrophil gelatinase‐associated lipocalin (NGAL) an early‐screening biomarker for ovarian cancer: NGAL is associated with epidermal growth factor‐induced epithelio‐mesenchymal transition
Authors: Lim Ratana , Ahmed Nuzhat , Borregaard Niels , Riley Clyde , Wafai Razan , Thompson Erik W. , Quinn Michael A. , Rice Gregory E. 
Published: February 2007

AbstractThe expression of neutrophil gelatinase‐associated lipocalin (NGAL) has been shown to be upregulated in ovarian cancer cells. In this study, we report that the expression of immunoreactive NGAL (irNGAL) in ovarian tumors changes with disease grade and that this change is reflected in the concentration of NGAL in peripheral blood. A total of 59 ovarian tissues including normal, benign, borderline malignant and grades 1, 2 and 3 malignant were analyzed using immunohistochemistry. irNGAL was not present in normal ovaries and the NGAL expression was weak to moderate in benign tissues. Both borderline and grade 1 tumors displayed the highest amount of NGAL expression with moderate to strong staining, whereas in grade 2 and 3 tumors, the extent of staining was significantly less (p < 0.01) and staining intensity was weak to moderate. Staining in all cases was confined to the epithelium. NGAL expression was analyzed by ELISA in 62 serum specimens from normal and different grades of cancer patients. Compared to control samples, the NGAL concentration was 2 and 2.6‐fold higher in the serum of patients with benign tumors and cancer patients with grade 1 tumors (p < 0.05) and that result was consistent with the expression of NGAL performed by Western blot. NGAL expression was evaluated by Western blot in an immortalized normal ovarian cell line (IOSE29) as well as ovarian cancer cell lines. Moderate to strong expression of NGAL was observed in epithelial ovarian cancer cell lines SKOV3 and OVCA433 while no expression of NGAL was evident in normal IOSE29 and mesenchyme‐like OVHS1, PEO.36 and HEY cell lines. NGAL expression was downregulated in ovarian cancer cell lines undergoing epithelio‐mesenchymal transition (EMT) induced by epidermal growth factor (EGF). Downregulation of NGAL expression correlated with the upregulation of vimentin expression, enhanced cell dispersion and downregulation of E‐cadherin expression, some of the hallmarks of EMT. EGF‐induced EMT phenotypes were inhibited in the presence of AG1478, an inhibitor of EGF receptor tyrosine kinase activity. These data indicate that NGAL may be a good marker to monitor changes of benign to premalignant and malignant ovarian tumors and that the molecule may be involved in the progression of epithelial ovarian malignancies. © 2007 Wiley‐Liss, Inc.
Circulating KL‐6/MUC1 mucin carrying sialyl Lewisa oligosaccharide is an independent prognostic factor in patients with lung adenocarcinoma
Authors: Inata Junya , Hattori Noboru , Yokoyama Akihito , Ohshimo Shinichiro , Doi Mihoko , Ishikawa Nobuhisa , Hamada Hironobu , Kohno Nobuoki 
Published: February 2007

AbstractMUC1 mucin is frequently observed in adenocarcinomas, and its association with metastasis has been postulated through the interaction between sialyl Lewis oligosaccharides present on this glycoprotein and selectins. Levels of soluble MUC1 recognized by anti‐KL‐6 monoclonal antibody were also frequently elevated in the sera of lung adenocarcinoma patients. The aim of this study was to demonstrate the presence of KL‐6/MUC1 carrying sialyl Lewisa oligosaccharide, designated as SLAK, and subsequently evaluate the clinical significance of circulating SLAK in patients with lung adenocarcinoma. We developed a sandwich ELISA system using anti‐sialyl Lewisa and anti‐KL‐6 antibodies to detect SLAK, and also measured circulating SLAK levels in 97 healthy controls and 103 patients with lung adenocarcinoma. Circulating SLAK levels were measured in the sera taken before treatment and then were evaluated to clarify whether such levels were related to the clinical outcomes. Levels of circulating SLAK were significantly higher in lung adenocarcinoma patients than in healthy subjects, and a higher serum SLAK level was correlated with the presence of distant metastasis. The overall survival rate for patients with high serum SLAK levels was significantly poorer than that of patients with low serum SLAK levels. The survival analysis restricted to the patients with distant metastasis also showed the same trend. In a multivariate survival analysis in lung adenocarcinoma patients, a high serum SLAK level was indicated as an independent prognostic factor. In conclusion, the circulating SLAK level at diagnosis is useful for predicting a poor prognosis in patients with lung adenocarcinoma. © 2007 Wiley‐Liss, Inc.
Neurotoxic activity of Gln49 phospholipase A2 from Gloydius ussuriensis snake venom
Authors: Chang Yan , Li Yingxue , Bao Yongming , An Lijia 
Published: February 2007

AbstractA novel neurotoxic protein phospholipase A2 (PLA2), molecular weight 13 881.83 Da, has been isolated from snake venom of Gloydius ussuriensis, named as Gln49‐PLA2, which shows weak lethal toxic, myotoxic and apparent anticoagulant activity, but lacks phospholipase activity. The Gln49‐PLA2 obviously induced an increase of the pain threshold in intoxicated 615 mice compared with the control group, suggesting it is a neurotoxin. Hot‐plate tests also showed that its analgesic activity was dose‐dependent, and naloxone antagonized the analgesic effect, implying the mechanism of action of Gln49‐sPLA2 is correlated with opioid receptors. Electrophysiology studies revealed decreases in the action potential and the nerve conduction velocity in isolated hoptoad (Bufo bufo gargarizans Cantor) sciatic nerve, indicating Gln49‐PLA2 most probably had effects on ion channels. Copyright © 2007 John Wiley & Sons, Ltd.
Micro processing with laser radiation – Trends and perspectives
Authors: Gillner Arnold 
Published: February 2007

AbstractMiniaturization and highly integrated functionalization are the driving factors in the production of innovative products in almost every industrial area today: Electronic components require conducting traces smaller than 100 μm und 3‐dimensional interconnections, highly fuel efficient cars are only possible by micro structured functional surfaces and injection nozzles with geometries <100 μm, medical products require selective functionalization for improved fluid control and micro optical components increase the functionality in a large variety of consumer products like mobile phones and miniaturized cameras.
Creating distinct value – How Coherent pursues further growth in laser markets
Authors: Meissner Paul 
Published: February 2007

AbstractIn the last decades, the laser business has seen tremendous progress but also the trouble of the telecom crisis. Today the business is steadily growing. This process is connected not only with expanding markets, but also with a rapid innovation cycle. LTJ spoke with Paul Meissner, Executive Vice President of Global Business Operations at Coherent Inc. about the strategy Coherent Inc. is pursuing in the competition for new markets and new ideas.
Characteristics of apathy in Parkinson's disease
Authors: Dujardin Kathy , Sockeel Pascal , Devos David , Delliaux Marie , Krystkowiak Pierre , Destée Alain , Defebvre Luc 
Published: February 2007

AbstractThe objective of this study was to use the Lille Apathy Rating Scale to assess apathy in a large population of Parkinson's disease (PD) patients and identify several different apathy profiles. One hundred fifty‐nine patients with probable PD and 58 healthy controls participated in the study. Apathy was assessed using the Lille Apathy Rating Scale. Motor, cognitive, and depressive symptoms were rated on standardized scales. Data were analyzed using linear regression and multivariate analyses of variance. Thirty‐two percent of the PD patients were classified as apathetic. Apathy was more frequent in patients with dementia. The four apathy dimensions contributed differently to the overall severity of the apathetic condition. Action initiation and intellectual curiosity had a marked influence. Linear regression analysis revealed that the apathy level was mainly determined by cognitive impairment, not associated with the severity of motor symptoms, and only associated with the apathy subcomponent of the Montgomery and Asberg Depression Rating Scale. Apathy is highly prevalent in PD patients. Apathy profiles vary according to the clinical presentation of PD. The high prevalence of apathy in PD suggests the involvement of frontal–subcortical circuits. Although the neurochemical substrate of apathy remains poorly characterized, the strong link between apathy and cognitive impairment observed in several studies suggests the participation of nondopaminergic circuits. © 2007 Movement Disorder Society
Synthesis, Morphology and Rheological Behavior of Fluoropolymer‐Polyacrylate Nanocomposites
Authors: Suresh Kattimuttathu I. , Pakula Tadeusz , Bartsch Eckhard 
Published: February 2007

AbstractNanocomposite materials composed of a PTFE copolymer core and an acrylic copolymer shell have been prepared by seeded emulsion polymerization. The effect of seed particle number and shell polymer composition on secondary particle nucleation and film formation ability of the dispersions has been studied. While TEM reveals a core‐shell structure present in the particles, AFM investigation of the film shows a nearly uniform dispersion of the fluorinated seed particles in a matrix formed by the shell polymer. Rheological measurements show composite behavior of the core‐shell latex films, especially at elevated temperatures, and an increase in viscosity and storage modulus when compared with the properties of the pure acrylic component. These composites exhibit a solid‐like behavior at lower frequencies (in the rubbery zone) indicating the formation of a network‐like structure which acts as a reinforcement for the acrylic matrix. The process takes place faster at higher temperatures, probably due to the increased mobility of the cores and a corresponding improvement of the mechanical properties is observed. The fluoropolymer‐PBMA nanocomposite films also show opalescent crystal like behavior due to the existence of a refractive index gradient.magnified image
Synthesis and Properties of a Superabsorbent Polymer Prepared by Copolymerization of Sodium Acrylate with Sodium 1‐(Acryloyloxy)propan‐2‐yl Phosphate
Authors: Chen Zhenbin , Liu Mingzhu , Qi Xiaohua 
Published: February 2007

AbstractA novel monomer, 1‐(acryloyloxy)propan‐2‐yl phosphoryl dichloride, was synthesized and characterized in this work. Thereafter, the monomer was neutralized with sodium hydroxide and copolymerized with sodium acrylate to obtain a superabsorbent polymer. The superabsorbent polymer was then modified to improve its swelling properties (i.e., the water absorbency under load, the hydrogel strength, the resilience and the dispersion). Both single factor and orthogonal design experiments were adopted to obtain optimal conditions. The superabsorbent polymer prepared under the optimal conditions showed improved water absorbency in physiological saline [17 g · g−1 under load (P = 2 × 103 Pa) and 65 g · g−1 at atmospheric pressure] and other swelling properties, such as hydrogel strength, resilience and dispersion, also improved.magnified image
Direction sensitive sensor probe for the evaluation of voluntary and reflex pelvic floor contractions
Authors: Constantinou Christos E. , Omata Sadao 
Published: February 2007

AbstractAimsThe development of a vaginal probe for the evaluation of the dynamics of pelvic floor function is described. Fundamental criteria in the design of this probe involves the incorporation of a means of assessing whether the isotonic forces closing the vagina are equally distributed or whether they are greater in some directions than others. The aim of this study is to present the design of directionally sensitive multi‐sensor probe, having circumferential spatial resolution, constructed to identify the distribution of anisotropic forces acting on the vagina following voluntary and reflex pelvic floor contractions.Materials and MethodsProbe system consists of four pairs of force/displacement sensors mounted on leaf springs enabling isotonic measurements of voluntary and reflex contractions. Assembly is retractable to 23 mm for insertion, and expandable to 60 mm for measurement. Simultaneous measurements were made of force and displacement with the sensors oriented in the anterior/posterior and left/right orientation of the vagina. Using this probe, measurements were carried out to identify the temporal and spatial characteristic response of the vaginal wall. Data were analyzed with respect to voluntary pelvic floor and cough‐induced contractions of nine subjects having a mean age of 64 years.ResultsA robust probe system was developed and measurements were successfully made. Initial results show that the maximum force and displacement occurs during reflex contractions in the anterior aspect of the vagina validating the anisotropic nature of the forces acting on the vaginal wall. The data also show that both the force and displacement produced by the cough‐induced has a higher magnitude than voluntary pelvic floor contraction.ConclusionsA directional multi‐sensor vaginal probe has been developed to evaluate the force and displacement produced during isotonic pelvic floor contractions. Analysis of the results provided new biomechanical data demonstrating the anisotropic nature of vaginal closure as a consequence of pelvic floor contractions. Neurourol. Urodynam. 26:386–391, 2007. © 2007 Wiley‐Liss, Inc.
Preparation and characterization of polyether‐block‐amide copolymer/clay nanocomposites
Authors: Yang I‐Kuan , Tsai Ping‐Hung 
Published: February 2007

AbstractA polyether‐block‐amide copolymer was successfully blended with eight organoclays and one sodium montmorillonite by melt processing technique to form nanocomposites. X‐ray diffraction, thermogravimetry, differential scanning calorimeter analysis, dynamic mechanical analysis, tensile test, and linear viscoelastic analysis were used to characterize the hybrids. The molecular structure of the surfactants in the organoclays was found having a significant impact on the viscoelasticity and the d‐spacing gain of the clays. Hybrids from organoclays using surfactants with a single long alkyl tail had a higher d‐spacing gain than those from organoclays using surfactants with two long alkyl tails. The melt viscoelasticity was found excellently correlated to the d‐spacing gain and hence the linear viscoelasticity could be an excellent indicator for platelet organization in the composites. The melt viscoelasticity is fairly correlated to the tensile modulus and glass transition temperature of the soft and hard segment, implying that the platelet organization plays a role in these properties. Properties such as melting point, thermal degradation temperature, elongation at break, and tensile strength are not correlated to the viscoelasticity. The failure indicates that these properties are irrelevant to or less influenced by the platelet organization. POLYM. ENG. SCI., 47:235–243, 2007. © 2007 Society of Plastics Engineers.
Supramolecular design in biopolymers and biomimetic polymers for advanced mechanical properties
Authors: Guan Zhibin 
Published: February 2007

AbstractThis mini review uses two examples to illustrate the importance of supramolecular chemistry in natural and biomimetic polymers for advanced mechanical properties. In the first example, dragline silk, one of the strongest and toughest natural fibers, uses intermolecular weak forces to self‐assemble into nanocomposites composed of β‐sheet nanocrystals imbedded in an amorphous matrix. In the second example, a load‐bearing protein, the sarcomere muscle protein titin, uses intramolecular weak forces to fold into repetitive modules for combined strength, toughness, and elasticity. Both examples show vividly that many natural polymers can combine important mechanical properties through programming supramolecular weak interactions into covalently formed biopolymers. This mini review attempts to summarize the current understanding of the molecular mechanisms that contribute to the exceptional mechanical properties for each natural polymer. Following that, the efforts from others and the author's own laboratory on developing synthetic polymers to mimic these natural counterparts are discussed. Copyright © 2007 Society of Chemical Industry