bluuebunny/crossref_metadata_2025_split huggingface dataset:
A New Lignan and Four New Lignan Glycosides from Mananthes patentiflora
Authors: Tian Junmian , Hao Xiaojiang , He Hongping 
Published: February 2006

AbstractA new lignan, 5‐hydroxyjusticidin A (= 9‐(1,3‐benzodioxol‐5‐yl)‐5‐hydroxy‐4,6,7‐trimethoxynaphtho[2,3‐c]furan‐1(3H)‐one; 1), and four new diphyllin‐type lignan glycosides, mananthosides C–F (2–5), containing glucosyl (Glc), arabinosyl (Ara), galactosyl (Gal), and/or apiosyl residues, have been isolated from Mananthes patentiflora, together with five known compounds. Their structures and configurations were elucidated by in‐depth 1D‐ and 2D‐NMR experiments, as well as MS analysis.
Facile One‐Pot Three‐Component Synthesis of Functionalized Pyridylfuran‐2‐amines
Authors: Adib Mehdi , Sayahi Mohammad Hosein , Koloogani Somayeh Aali , Mirzaei Peiman 
Published: February 2006

AbstractThe reactive 1 : 1 zwitterionic intermediates generated in situ from the reaction between a series of isocyanides and diaroylacetylenes were trapped by pyridine carbaldehydes to yield highly functionalized 5‐pyridylfuran‐2‐amines in good yields (82–93%).
Synthesis of a Phosphorylated Disaccharide Fragment of the O‐Specific Polysaccharide of Vibrio cholerae O139, Functionalized for Conjugation
Authors: Ruttens Bart , Kováč Pavol 
Published: February 2006

AbstractThe title disaccharide, 2‐{2‐{2‐[(2‐ethoxy‐3,4‐dioxocyclobut‐1‐en‐1‐yl)amino]ethoxy}ethoxy}ethyl 2‐O‐(3,6‐dideoxy‐α‐L‐xylo‐hexopyranosyl)‐β‐d‐galactopyranoside cyclic 4,6‐(potassium phosphate) (2), was synthesized from the two isomeric linker‐equipped galactose acceptors 9 and 10, obtained by phosphorylation of 2‐[2‐(2‐azidoethoxy)ethoxy]ethyl 3‐O‐benzyl‐β‐d‐galactopyranoside (8), which were glycosylated with ethyl 2,4‐di‐O‐benzyl‐3,6‐dideoxy‐1‐thio‐β‐l‐xylo‐hexopyranoside (12; Scheme). Mainly the fully protected α‐(1 → 2)‐linked products 13α and 14α were formed. Catalytic hydrogenolysis/hydrogenation effected global deprotection, thereby removing the chirality at the P‐atom, and simultaneously converted the azido group in the linker to an amino group (→ 15). Final treatment with diethyl squarate (= 3,4‐diethoxycyclobut‐3‐ene‐1,2‐dione) gave target compound 2, amenable for conjugation to proteins.
Hierarchic Supramolecular Interactions within Assemblies in Solution and in the Crystal of 2,3,6,7‐Tetrasubstituted 5,5′‐(Anthracene‐9,10‐diyl)bis[pyrimidin‐2‐amines]
Authors: Balaban Teodor Silviu , Eichhöfer Andreas , Krische Michael J. , Lehn Jean‐Marie 
Published: February 2006

AbstractThe title compounds 6 and 7 were synthesized in good yield (Schemes 1 and 2), and their mode of assembly was studied both in solution, for the tetrakis(decyloxy) derivative 6, and in the crystal, for the tetramethoxy analogue 7. The pyrimidin‐2‐amine moieties of 6 and 7 can engage in three different supramolecular interactions: i) metal ligation via one of the pyrimidine N‐atoms, ii) cooperative double H‐bonding via the NH2 group, and iii) π–π‐stacking interactions. In solution, coordination of the central Zn‐atom within the soluble porphyrinatozinc complex 19 leads to significant changes in the NMR and absorption spectra of 6. In the absence of metal ligation, the next strongest interaction is H‐bonding which can operate in nonpolar or moderately polar solvents. In these cases, however, no stacking interaction or inclusion compounds could be put into evidence in the case of 6 by absorption, fluorescence, or NMR spectroscopies. The π‐stacking interactions were only observed in the crystal of 7 in conjunction with double H‐bonding. Slightly disordered DMSO molecules are also H‐bonded to the NH2 groups of 7, perturbing the expected packing. The present study illustrates some of the challenges inherent to directing hierarchical assembly processes in the solid state.
Transformation of 5‐Hydroxy‐ to (5‐Chloropentanoyl)amino Derivatives under ‘Direct Amide Cyclization’ Conditions
Authors: Iliev Boyan , Verma Sanjiv , Linden Anthony , Heimgartner Heinz 
Published: February 2006

AbstractThe application of the ‘direct amide cyclization’ conditions to the linear δ‐hydroxy diamide 11 is described (Scheme 3). Instead of the cyclization to the expected nine‐membered cyclodepsipeptide, only the chloro acid 12 was obtained. Its formation could be explained by consecutive formation of the 1,3‐oxazol‐5(4H)‐one 16 and the six‐membered imino lactone 17 as intermediates (Scheme 4). The spontaneous isomerization of the latter gave 12 in a good yield.
Under the microscope: the structure of the foreign exchange market
Authors: Sager Michael J. , Taylor Mark P. 
Published: February 2006

AbstractWe provide a detailed, up‐to‐date description of the microstructure of the foreign exchange market and of the behaviour of participant groups. In the light of this, we highlight shortcomings in existing theoretical models of market interaction and present an outline alternative model that marries theoretical prediction and current market practice. Copyright © 2006 John Wiley & Sons, Ltd.
Understanding order flow
Authors: Evans Martin D. D. , Lyons Richard K. 
Published: February 2006

AbstractThis paper develops a model for understanding end‐user order flow in the FX market. The model addresses several puzzling findings. First, the estimated price‐impact of flow from different end‐user segments is, dollar‐for‐dollar, quite different. Second, order flow from segments traditionally thought to be liquidity‐motivated actually has power to forecast exchange rates. Third, about one‐third of order flow's power to forecast exchange rates 1 month ahead comes from flow's ability to forecast future flow, whereas the remaining two‐thirds applies to price components unrelated to future flow. We show that all of these features arise naturally from end‐user heterogeneity, in a setting where order flow provides timely information to market‐makers about the state of the macro‐economy. Copyright © 2006 John Wiley & Sons, Ltd.
Explaining trading volume in the euro
Authors: Brzeszczynski Janusz , Melvin Michael 
Published: February 2006

AbstractFollowing the introduction of the euro in 1999, daily trade volume began a downward trend until early 2002, after which daily volume started to trend upward. A model of weekly trades suggests that changes in momentum as well as the carry trade motives of interest differentials are significant explanatory factors. Daily data examination reveals that Fridays have lower activity, and Tuesdays greater activity than average. At the intradaily level, trading is very low before and after London business hours. Within the London business day, trade activity is higher in 5‐min intervals when a ‘big figure’ is breached. This is consistent with stop‐loss or take‐profit motives for trading. Copyright © 2006 John Wiley & Sons, Ltd.
Activation of cell‐survival transcription factor NFκB in L1Ig6‐stimulated endothelial cells
Authors: Reidy Martin , Zihlmann Pius , Hubbell Jeffrey A. , Hall Heike 
Published: February 2006

AbstractLigation of the integrin αvβ3 in endothelial cells has been shown to be important for their survival. Such ligation induces signalling events merging into the Raf‐Ras‐ERK cascade that eventually induces activation of nuclear factor kappa B (NFκB), leading to its phosphorylation and nuclear translocation and thus inhibiting apoptosis. Here, the recombinant sixth immunoglobulin‐like domain of cell adhesion molecules L1 (L1Ig6), a ligand for integrin αvβ3, was explored as a component of vascular implant surfaces to initiate the NFκB‐cell survival pathway. This supposition was supported. Specifically, NFκB‐p65 was expressed in human umbilical vein endothelial cells (HUVECs) and when stimulated on L1Ig6, the phosphorylated form was found in the nucleus in over 60% of the cells. NFκB was not translocated into the nucleus on a number of other extracellular matrix substrates examined or when fibroblasts were cultured on L1Ig6. NFκB phosphorylation and nuclear translocation could be inhibited by blocking ligation of αvβ3 by L1Ig6 with an antibody recognizing αvβ3, with a cyclic RGD peptide, and with soluble L1Ig6. Moreover, blocking of αvβ3 interaction with L1Ig6 was correlated with induction of apoptosis. Thus, these experiments demonstrate that L1Ig6 may be useful as αvβ3 ligand for the induction of endothelial survival pathways mediated by NFκB‐p65. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Energetics of osmoregulation: I. oxygen consumption by Fundulus heteroclitus
Authors: Kidder George W. , Petersen Christopher W. , Preston Robert L. 
Published: February 2006

AbstractWe have developed a flow‐through method for measuring oxygen consumption in fish which allows continuous monitoring over periods of days with good accuracy. Our goal was to determine the changes in basal metabolic rate in estuarine fish as a function of salinity. We show that in Fundulus heteroclitus, the oxygen consumption drops by 50% during the first 12 hr in the respirometer, as the fish cease exploratory movements. We have determined the influence of temperature and body size on resting respiratory rate, but failed to find any circadian or tidal rhythm in aerobic respiration. With these variables controlled, we determined that changing from 10 to 30 ppt water had no demonstrable effect on oxygen uptake. Since there must be a large change in osmotic flux due to this change in salinity, it appears that the fish might be diverting energy from other uses rather than increasing aerobic energy production to meet the increased osmoregulatory work load. J. Exp. Zool. 305A:309–317, 2006. © 2006 Wiley‐Liss, Inc.
Effect of protein kinase C inhibitors on porcine oocyte activation
Authors: Sedmíková Markéta , Rajmon Radko , Petr Jaroslav , Švestková Dana , Chmelíková Eva , Akal Astatike Bantirgu , Rozinek JIří , Jílek František 
Published: February 2006

AbstractThe effect of protein kinase C (PKC) inhibitors on porcine oocyte activation by calcium ionophore A23187 was studied. Calcium ionophore applied in a 50 µM concentration for 10 min induced activation in 74% of oocytes matured in vitro. When the ionophore‐treated oocytes were exposed to the effect of bisindolylmaleimide I, which inhibits calcium‐dependent PKC isotypes (PKC‐α, ‐βI, ‐βII, ‐γ,) and calcium‐independent PKC isotypes (PKC‐δ, ‐ε), the portion of activated oocytes decreased (at a concentration of 100 nM, 2% of the oocytes were activated). Go6976, the inhibitor of calcium‐dependent PKC isotypes PKC‐α, ‐βI did not prevent the action of the oocytes treated with calcium ionophore in concentrations from 1 to 100 µM. The inhibitor of PKC‐βI and βII isotypes, hispidin, in a concentration of 2 µM–2 mM, was not effective either. The inhibitor of PKC‐δ isotype, rottlerin, suppressed activation of the oocytes by calcium ionophopre (no oocyte was activated at 10 µM concentration). The PKC‐δ isotype in matured porcine oocytes, studied by Western blot analysis, appeared as nontruncated PKC‐δ of 77.5 kDa molecular weight, on the one hand, and as truncated PKC‐δ, which was present in the form of a doublet of approximately 62.5 and 68 kDa molecular weight, on the other hand. On the basis of these results, it can be supposed that PKC participates in the regulation of processes associated with oocyte activation. Calcium‐dependent PKC‐α, ‐β isotypes do not seem to play any significant role in calcium activation. The activation seems to depend on the activity of the calcium‐independent PKC‐δ isoform. J. Exp. Zool. 305A:376–382, 2006. © 2006 Wiley‐Liss, Inc.
Effect of prevention of lung inflation on metamorphosis and respiration in the developing bullfrog tadpole, Rana catesbeiana
Authors: Gdovin Matthew J. , Jackson Vonnie V. , Zamora Debora A. , Leiter James C. 
Published: February 2006

AbstractWe tested the hypothesis that respiratory development would be retarded in tadpoles reared in aquaria in which a barrier prevented access to the air–water interface. To test this hypothesis, we examined swimming behavior and respiration in intact tadpoles and gill and lung respiratory activity and central chemosensory responses in an in vitro brainstem preparation. The “barrier” tadpoles had significantly lower resting gill frequencies and higher lung breath attempts than control tadpoles at the same metamorphic stage. Control tadpoles swam greater distances and spent more time in the upper one third of the aquaria, while barrier tadpoles spent significantly more time at the bottom of the aquaria. There was significantly greater mortality for barrier tadpoles compared to control animals in the earliest and latest metamorphic stages. Mean body weight was significantly greater, and metamorphic rate was reduced in barrier tadpoles. Neither control nor barrier tadpole brainstem preparations demonstrated a gill ventilatory response to CO2; however, both control and barrier preparations possessed significant lung frequency responses to central CO2 chemoreceptor stimulation. Bath application of the GABAA and glycine receptor antagonists, bicuculline and strychnine, had greater effects on control tadpole gill burst activity and produced a similar large‐amplitude bursting pattern in both control and barrier tadpoles, that was insensitive to CO2 chemoreceptor stimulation. We conclude that development of the respiratory pattern was perturbed by the barrier, but the major effect was on gill ventilation rather than lung ventilation as we had expected. J. Exp. Zool. 305A:335–347, 2006. © 2006 Wiley‐Liss, Inc.
Astrocyte–neuron vulnerability to prenatal stress in the adult rat brain
Authors: Barros Virginia G. , Duhalde‐Vega Maite , Caltana Laura , Brusco Alicia , Antonelli Marta C. 
Published: February 2006

AbstractChronic activation of the stress response during pregnancy has been shown to be injurious to the development of the offspring. We have previously demonstrated that restraint prenatal stress inflicted during the last week of pregnancy in rats increased dopamine and glutamate receptors in forebrain areas of the adult offsprings. In this study, the same prenatal insult was employed to assess morphological changes in astrocytes and in the dendritic arborization in frontal cortex, striatum, and hippocampus of the adult rat brain. On postnatal day 90, brains were processed for immunocytochemistry using primary antibodies to glial fibrillary acidic protein (GFAP; the main cytoskeletal astroglial protein), S100B protein (an astroglial‐derived neurotrophic factor), MAP‐2 (a microtubule‐associated protein present almost exclusively in dendrites), and synaptophysin (Syn; one major integral protein of the synaptic vesicles membrane). The results show a significant increase in the cell area of GFAP‐immunoreactive (‐IR) astrocytes, with high levels of S100B protein and a significant decrease in the relative area of MAP‐2‐IR neuronal processes in prenatally stressed adult rats. The expression of synaptophysin decreased in all areas studied. These results demonstrate that prenatal stress induces a long‐lasting astroglial reaction and a reduced dendritic arborization, with synaptic loss in the brain of adult offspring. In addition to the neurochemical alterations previously reported, these morphological changes might be underlying the behavioral and learning impairment previously observed in prenatally stressed rats. © 2006 Wiley‐Liss, Inc.
Specificity and divergence in the neurobiologic effects of different metallothioneins after brain injury
Authors: Penkowa Milena , Tio Laura , Giralt Mercedes , Quintana Albert , Molinero Amalia , Atrian Silvia , Vašák Milan , Hidalgo Juan 
Published: February 2006

AbstractBrain injury and neuroinflammation are pathophysiologic contributors to acute and chronic neurologic disorders, which are progressive diseases not fully understood. Mammalian metallothioneins I and II (MT‐I&II) have significant neuroprotective functions, but the precise mechanisms underlying these effects are still unknown. To gain insight in this regard, we have evaluated whether a distant, most likely single‐domain MT (Drosophila MTN) functions similarly to mammalian MT‐I&II (recombinant mouse MT‐I and human MT‐IIa and native rabbit MT‐II) after cryogenic injury to the cortex in Mt1&2 KO mice. All the recombinant proteins showed similar neuroprotective properties to native MT‐II, significantly reducing brain inflammation (macrophages, T cells, and pro‐inflammatory cytokines), oxidative stress, neurodegeneration, and apoptosis. These results in principle do not support specific protein–protein interactions as the mechanism underlying the neuroprotective effects of these proteins because a non‐homologous and structurally unrelated MT such as Drosophila MTN functions similarly to mammalian MTs. We have also evaluated for the first time the neurobiologic effects of exogenous MT‐III, a major CNS MT isoform. Human rMT‐III, in contrast to human nMT‐IIa, did not affect inflammation, oxidative stress, and apoptosis, and showed opposite effects on several growth factors, neurotrophins, and markers of synaptic growth and plasticity. Our data thus highlight specific and divergent roles of exogenous MT‐III vs. the MT‐I&II isoforms that are consistent with those attributed to the endogenous proteins, and confirm the suitability of recombinant synthesis for future therapeutic use that may become relevant to clinical neurology. © 2006 Wiley‐Liss, Inc.
Improvement of port wine stain laser therapy by skin preheating prior to cryogen spray cooling: A numerical simulation
Authors: Jia Wangcun , Aguilar Guillermo , Verkruysse Wim , Franco Walfre , Nelson J. Stuart 
Published: February 2006

AbstractBackground and ObjectivesAlthough cryogen spray cooling (CSC) in conjunction with laser therapy has become the clinical standard for treatment of port wine stain (PWS) birthmarks, the current approach does not produce complete lesion blanching in the vast majority of patients. The objectives of this study are to: (1) experimentally determine the dynamic CSC heat flux when a skin phantom is preheated, and (2) numerically study the feasibility of using skin preheating prior to CSC to improve PWS laser therapeutic outcome.Study Design/Materials and MethodsA fast‐response thin‐foil thermocouple was used to measure the surface temperature and thus heat flux of an epoxy skin phantom during CSC. Using the heat flux as a boundary condition, PWS laser therapy was simulated with finite element heat diffusion and Monte Carlo light distribution models. Epidermal and PWS blood vessel thermal damage were calculated with an Arrhenius‐type kinetic model.ResultsExperimental results show that the skin phantom surface can be cooled to a similar minimum temperature regardless of the initial temperature. Numerical simulation indicates that upon laser irradiation, the epidermal temperature increase is virtually unaffected by preheating, while higher PWS blood vessel temperatures can be achieved. Based on the damage criterion we assumed, the depth and maximum diameter of PWS vessels that can be destroyed irreversibly with skin preheating are greater than those without.ConclusionsSkin preheating prior to CSC can maintain epidermal cooling while increasing PWS blood vessel temperature before laser irradiation. Numerical models have been developed to show that patients may benefit from the skin preheating approach, depending on PWS vessel diameter and depth. Lasers Surg. Med. 38:155–162, 2006. © 2006 Wiley‐Liss, Inc.
Direct Ion Exchange Self‐Metallization: A Novel and Efficient Route for the Preparation of Double‐Surface‐Silvered Polyimide Films
Authors: Qi Shengli , Wu Dezhen , Bai Zongwu , Wu Zhanpeng , Yang Wantai , Jin Riguang 
Published: February 2006

AbstractSummary: Silvered polyimide films have been fabricated by direct ion exchange of a damp‐dry poly(amic acid) film with an aqueous silver solution such as silver nitrate. Thermal curing of the silver(I)‐containing films under tension leads to cycloimidization of the poly(amic acid) into polyimide with a concomitant silver(I) reduction and aggregation at both film sides to give reflective and conductive double‐surface‐silvered polyimide films. The metallized films retain the essential properties of the parent polyimide.Surface morphology of the prepared double‐surface‐silvered polyimide films.magnified imageSurface morphology of the prepared double‐surface‐silvered polyimide films.
Innovationen durch PACVD Duplex Schichtsysteme im Leichtmetall‐Druckguss
Authors: Klimek K. S. , Gebauer‐Teichmann A. , Röders G. , Kaestner P. , Rie K.‐T. 
Published: February 2006

AbstractDuplex‐PACVD Hartstoff‐Beschichtungen haben sich bereits bewährt zur Standzeiterhöhung von Werkzeugen im Hinblick auf Adhäsion, Verschleiß, Ermüdung und Korrosion von Stahl.Die Entwicklung der Synthese von Duplex nanostrukturierten und gradierten Schichtsystemen basierend auf Boriden und Nitriden des Titans wird beschrieben. Ziel dieser Untersuchung ist die Optimierung der Oberflächeneigenschaften mittels Neu‐ bzw. Weiterentwicklung und Kombination von Plasmaoberflächenprozessen: Duplex‐Prozess und Gradientenschichten.Insbesondere Duplex‐Hartstoffschichten werden hier im PACVD‐Verfahren abgeschieden und im Hinblick auf ihre tribologischen Eigenschaften untersucht und im Aluminium‐ und Magnesiumdruckguss eingesetzt. Gleichzeitig werden Sprühmittelmengen und Formaushebeschrägen reduziert. Praktische Tests wurden von Automobilherstellern und Zulieferern durchgeführt. Alle Beschichtungen auf Druckgusswerkzeugen zeigten eine deutliche Standzeiterhöhung und geringere Metallanklebungstendenz. Beschichtete Werkzeuge waren bei geringerer Trennmittelmenge den unbeschichteten Werkzeugen bei ursprünglicher Trennmittelmenge überlegen. Die Wirtschaftlichkeit beschichteter Druckgusswerkzeuge konnte bewiesen werden.
Rost‐ und säurebeständige Stähle unter Komplexbeanspruchung
Authors: Ellermeier J. , Gugau M. , Scholz M. , Berger C. , Schlücker E. , Depmeier L. 
Published: February 2006

AbstractDie Schwingungsrisskorrosionsbeständigkeit zweier Stähle (Superaustenit (1.3974) und ein Duplexstahl (1.4462)) wurde anhand von Zugschwell‐, Umlaufbiege‐, Scheiteldruckschwell‐ und Innendruckschwellversuchen vergleichend untersucht. Die Untersuchungen wurden in 10 % Salpetersäure, in künstlichem Meerwasser nach DIN 50905 und in den beiden für die Praxis besonders relevanten Medien Kaliumjodidlösung und H2S‐begastem künstlichen Meerwasser nach DIN 50905 und zum Vergleich in säurefreiem Spindelöl durchgeführt. Die Ergebnisse belegen, dass der Werkstoff 1.3974 unter ein‐ und dreiachsiger Beanspruchung bis 107 Schwingspiele eine deutlich höhere Schwingungsrisskorrosionsbeständigkeit als der Werkstoff 1.4462 aufweist. Es wurde ein Korrosionsfaktor ermittelt, der das Verhältnis aus den Versuchen in den korrosiven Medien im Vergleich zu den Ergebnissen in säurefreiem Spindelöl beschreibt. In künstlichem Meerwasser nach DIN 50905 ergibt sich ein Faktor zwischen 0,67 und 0,92 in Abhängigkeit der Beanspruchung für den Werkstoff 1.4462. In 10 % Salpetersäure ergibt sich für den Werkstoff 1.4462 ein Faktor zwischen 0,67 und 0,83. Beim Werkstoff 1.3974 wird ein Faktor von 0,86‐1 in künstlichem Meerwasser nach DIN 50905 und von 0,70‐1,0 in 10 % Salpetersäure ermittelt.