bluuebunny/crossref_metadata_2025_split huggingface dataset:
A co‐ordinate system independent streamwise upwind method for fluid flow computation
Authors: Ferziger Joel H. , Tseng Yu‐heng 
Published: May 2004

AbstractA new co‐ordinate invariant streamwise upwind formulation for convection dominated flows is developed. The eddy diffusivity/viscosity is added directly to the equations in order to remove the oscillations in the solution. The equations then can be solved by any high‐order scheme and the solution retains the accuracy of the high‐order scheme. The accuracy and reduced lateral thickness growth rate are demonstrated with several numerical examples, including pure convective flows and lid‐driven cavity flow. The lateral spreading due to the numerical diffusion is controlled by the anisotropic tensor. Copyright © 2004 John Wiley & Sons, Ltd.
Neurogenic phenotypes induced by RNA interference with bHLH genes of the Enhancer of split complex of Drosophila melanogaster
Authors: Nagel Anja C. , Maier Dieter , Krauß Sonia , Mezger Markus , Preiss Anette 
Published: May 2004

AbstractSummary: The Enhancer of split gene complex [E(spl)‐C] of Drosophila melanogaster harbors seven highly related genes encoding transcriptional regulators with a basic helix‐loop‐helix (bHLH) domain. They are activated by the Notch signaling pathway in order to inhibit proneural gene activity, for example, during neurogenesis in the developing embryo. The E(spl) proteins are at least partly redundant, despite some remarkable differences in their expression patterns. We attempted to address the degree of redundancy by means of RNA interference. We find a quantitative correlation between the degree of a neurogenic phenotype and the number of genes affected. Surprisingly, interference with m3 results in a high rate of mortality which cannot be reproduced by genetic mutation. Most likely, m3 dsRNA interferes with unrelated genes involved in other aspects of embryonic development. genesis 39:105–114, 2004. © 2004 Wiley‐Liss, Inc.
Long‐range effect of upd, a ligand for Jak/STAT pathway, on cell cycle in Drosophila eye development
Authors: Tsai Yu‐Chen , Sun Y. Henry 
Published: May 2004

Abstractunpaired (upd) encodes a ligand for the Jak/STAT signaling pathway in Drosophila. In the second instar and early third larval eye disc, upd is expressed in the center of the posterior margin. upd loss‐of‐function mutations caused eye size reduction and upd overexpression caused eye enlargement. Upd regulates eye size through the Dome/Jak(Hop)/STAT92 signaling pathway to promote cell proliferation. Interestingly, the effect of Upd is only on cells located anterior to the morphogenetic furrow (MF), but has no effect on the second mitotic wave, which is posterior to MF. Overexpression of upd behind MF can nonautonomously induce cell proliferation up to 20 rows of cells anterior to MF. The G1 cyclin, cycD transcript level was also enhanced anterior to MF. Consistent with the long‐range effect, we found that the extracellular Upd protein can be detected over a comparable long range, suggesting that Upd acts directly over a long distance as a signaling molecule. genesis 39:141–153, 2004. © 2004 Wiley‐Liss, Inc.
Laser microdissection reveals regional and cellular differences in GFAP mRNA upregulation following brain injury, axonal denervation, and amyloid plaque deposition
Authors: Burbach Guido J. , Dehn Doris , Del Turco Domenico , Staufenbiel Matthias , Deller Thomas 
Published: May 2004

AbstractAstrocytes are one of the major cell types responding to central nervous system injury. Upregulation of the astrocytic intermediate filament molecule glial fibrillary acidic protein (GFAP) is a key event associated with this reaction. To study the response of astrocytes to different types of brain lesions, GFAP mRNA expression was analyzed by quantitative reverse transcription‐polymerase chain reaction (qRT‐PCR) in mouse brain following injury, axonal denervation (entorhinal cortex lesion), and amyloid plaque deposition (APP23 transgenic mice). Analysis of tissue areas surrounding a lesion revealed a 21‐fold increase of GFAP mRNA in tissue surrounding an injury site, a 6‐fold increase in denervated tissue areas, and a 5‐fold increase in plaque containing tissue. To this GFAP mRNA increase, astrocytic proliferation and migration as well as an increase of cellular GFAP mRNA expression within astrocytes could have contributed. To determine the degree of GFAP mRNA upregulation in individual astrocytes, an immunofluorescence protocol was developed to harvest astrocytes selectively by laser microdissection and preserve intact RNA. qRT‐PCR analysis of GFAP mRNA in microdissected astrocytes revealed an 82‐fold increase in astrocytes surrounding an injury site, a 30‐fold increase in astrocytes located in a denervation zone, and an 18‐fold increase in astrocytes surrounding an amyloid plaque. These data demonstrate that GFAP mRNA is strongly upregulated within individual reactive astrocytes in response to a lesion. Because astrocytic GFAP mRNA upregulation differs among the three lesioning paradigms, we conclude that the lesion type is an important determinant of postlesional astrocytic reactivity. © 2004 Wiley‐Liss, Inc.
Thrombin induces expression of cytokine‐induced SH2 protein (CIS) in rat brain astrocytes: Involvement of phospholipase A2, cyclooxygenase, and lipoxygenase
Authors: Ji Kyung‐ae , Yang Myung‐Soon , Jou Ilo , Shong Min‐Ho , Joe Eun‐Hye 
Published: May 2004

AbstractPreviously we have reported that thrombin induces inflammatory mediators in brain glial cells (Ryu et al. 2000. J Biol Chem 275:29955). In the present study, we found that thrombin induced a negative regulator of a cytokine signaling molecule, cytokine‐induced SH2 protein (CIS), in rat brain astrocytes. In response to thrombin, CIS expression was increased at both the mRNA and protein levels. Although STAT5 is known to regulate CIS expression, thrombin did not activate STAT5, and inhibitors of JAK2 (AG490) and JAK3 (WHI‐P97 and WHI‐P154) had little effect on thrombin‐induced CIS expression. In contrast, cytosolic phospholipase A2 (cPLA2), cyclooxygenase (COX), and lipoxygenase (LO) play a role in CIS expression, since inhibitors of cPLA2, cyclooxygenase (COX), and LO significantly reduced CIS expression. Reactive oxygen species (ROS) scavengers (N‐acetyl‐cysteine [NAC] and trolox) reduced thrombin‐induced CIS expression, and inhibitors of COX and LO reduced ROS produced by thrombin. Furthermore, prostaglandin E2 (PGE2) and leukotriene B4 (LTB4), products of COX and LO, respectively, potentiated thrombin‐induced CIS expression, indicating that ROS, and PGE2 and LTB4 generated by COX and LO, mediate CIS expression. Since interferon‐γ (IFN‐γ)‐induced GAS‐luciferase activity and tyrosine phosphorylation of STAT1 and STAT3 were lower in CIS‐transfected cells compared to control vector‐transfected cells, CIS could have anti‐inflammatory activity. These data suggest that thrombin‐stimulation of ROS and prostaglandin and leukotriene production via the cPLA2, COX and LO pathways results in CIS expression. More importantly, CIS expression may be a negative feedback mechanism that prevents prolonged inflammatory responses. © 2004 Wiley‐Liss, Inc.
Two Novel Triterpenes from the Leaves of Ficus microcarpa
Authors: Kuo Yueh‐Hsiung , Lin Huan‐You 
Published: May 2004

AbstractTwo novel triterpenes, 29(20→19)abeolupane‐3,20‐dione (4) and 19,20‐secoursane‐3,19,20‐trione (5), besides (3β)‐3‐hydroxy‐29(20→19)abeolupan‐20‐one (2), lupenone, and α‐amyrone (6), were isolated from the leaves of Ficus microcarpa and were characterized by spectroscopic means, including 2D‐NMR techniques and chemical methods. Compound 4 is the second derivative having the 29(20→19)abeolupane skeleton, and 5 is a novel skeleton. A biosynthetic pathway to 5 is proposed (Scheme).
Relaxivity and Transmetallation Stability of New Benzyl‐Substituted Derivatives of GadoliniumDTPA Complexes
Authors: Laurent Sophie , Botteman François , Elst Luce Vander , Muller Robert N. 
Published: May 2004

AbstractIn our efforts of finding new specific contrast agents of higher relaxivity and selectivity, we have prepared the two new benzyl‐functionalized DTPA (‘diethylenetriamine pentaacetate’) gadolinium complexes (S)‐3 and (R,S)‐4, and compared their properties with those of the known regioisomers (S)‐2 and (S)‐1. The theoretical fitting of the reduced transverse relaxation rates of the 17O‐nucleus of H2O gave values for the water‐residence time (τM) of 86–143 ns at 310 K, values that are not limiting the proton relaxivity at body temperature. 1H‐NMRD (nuclear magnetic‐relaxation dispersion) Profiles showed that the relaxivity of 1–4 (r1=4.3–5.1 s−1 mM−1 at 20 MHz and 310 K) is higher than for the GdDTPA parent compound 5. Transmetallation assessment demonstrated that all substituted compounds, except for (S)‐2, are more stable than 5. The highest stability towards Zn2+‐induced transmetallation was achieved with complexes 3, 1, and 4 (in decreasing order). Apparently, the steric hindrance of the benzyl substituents in positions 5, 4, and 2, respectively, favorably reduces the accessibility of Zn ions. From a synthetic point of view, 4‐substituted DTPA complexes of type 1 are more readily accessible than 5‐substituted compounds of type 3. Therefore, the former seem to be superior for linking substituted DTPA complexes to macromolecules or specific vectors.
Donor‐Substituted Perethynylated Dehydroannulenes and Radiaannulenes: Acetylenic Carbon Sheets Featuring Intense Intramolecular Charge Transfer
Authors: Mitzel Frieder , Boudon Corinne , Gisselbrecht Jean‐Paul , Seiler Paul , Gross Maurice , Diederich François 
Published: May 2004

AbstractIn this article, we report the preparation of unprecedented π‐conjugated macrocycles (Fig. 1) by acetylenic scaffolding using modular tetraethynylethene (TEE, 3,4‐diethynylhex‐3‐ene‐1,5‐diyne) building blocks. A novel photochemical access to (Z)‐bisdeprotected TEEs (Scheme 1) enabled the synthesis of the anilino‐substituted perethynylated octadehydro[12]‐ (5) and dodecadehydro[18]annulenes (6) (Scheme 2). Following the serendipitous discovery of perethynylated radiaannulenes (Scheme 3) that can be viewed as hybrids between perethynylated dehydroannulenes and expanded radialenes, two series of monocyclic (7–9; Scheme 6) and bicyclic (10 and 11; Scheme 7) representatives were prepared. Substantial strain in the macrocyclic perimeter of radiaannulene 7 was revealed by X‐ray crystal‐structure analysis (Fig. 2). Nevertheless, mono‐ and bicyclic radiaannulenes are stable at room temperature in air for months. The opto‐electronic properties of both dehydroannulenes and radiaannulenes are substantially enhanced by the introduction of the peripheral anilino donor groups that undergo strong intramolecular charge‐transfer interactions with the electron‐accepting all‐C cores. As a result, the UV/VIS spectra feature intense, bathochromically shifted charge‐transfer bands that disappear upon protonation of the anilino moieties and are fully recovered upon neutralization (Figs. 4–9). A comparison between anilino‐substituted perethynylated dehydroannulenes, expanded radialenes, and radiaannulenes revealed that the efficiency of the intramolecular charge‐transfer interaction strongly depends on the structure of the electron‐accepting all‐C perimeter. Electrochemical investigations (Table) demonstrated that the radiaannulenes are particularly powerful electron acceptors. Thus, bicyclic radiaannulene 11, which possesses eight peripheral 3,5‐di(tert‐butyl)phenyl substituents, is reversibly reduced at −0.83 V in THF (vs. Fc+/Fc), making it a better electron acceptor than buckminsterfullerene C60 under comparable conditions.
Synthesis, Characterization, and DNA‐Binding Properties of the Ruthenium(II) Complexes [Ru(dipn)(dptp)](ClO4)2 and [Ru(dipn)(pat)](ClO4)2 (dipn=N‐(3‐Aminpropyl)propane‐1,3‐diamine; dptp=2‐(5,6‐Diphenyl‐1,2,4‐triazin‐3‐yl)‐1,10‐phenanthroline; pat=9‐(1,10‐Phenanthrolin‐2‐yl)acenaphtho[1,2‐e][1,2,4]triazine)
Authors: Hong Xian‐Lan , Chao Hui , Lin Li‐Jun , Zheng Kang‐Cheng , Li Hong , Wang Xiang‐Li , Yun Feng‐Cun , Ji Liang‐Nian 
Published: May 2004

AbstractTwo novel tridentate ruthenium(II) complexes containing an asymmetric heteroaromatic and a polyamine ligand, [Ru(dipn)(dptp)](ClO4)2 (1⋅2 $\rm{ ClO_4^ -}$) and [Ru(dipn)(pat)](ClO4)2 (2⋅2 $\rm{ ClO_4^ -}$) (dipn=N‐(3‐aminopropyl)propane‐1,3‐diamine; dptp=2‐(5,6‐diphenyl‐1,2,4‐triazin‐3‐yl)‐1,10‐phenanthroline; and pat=9‐(1,10‐phenanthrolin‐2‐yl)acenaphtho[1,2‐e][1,2,4]triazine) were synthesized and characterized by elemental analysis, ESI‐MS, 1H‐NMR, UV/VIS, and cyclic voltammetry. The DNA‐binding behavior of both complexes was studied by absorption titration, thermal denaturation, and viscosity measurements. Results indicate that complex 2 binds to calf‐thymus DNA in an intercalative mode but complex 1 binds to DNA in partial intercalation, and the DNA‐binding affinity of complex 2 is much greater than that of complex 1. Theoretical studies for these complexes were also carried out with the density‐functional‐theory (DFT) method. The trend in the DNA‐binding affinity and some electrochemical and spectral properties of the complexes can be further explained applying the DFT computational results.
2‐Amino‐8‐(2‐deoxy‐2‐fluoro‐β‐D‐arabinofuranosyl)imidazo[1,2‐a]‐1,3,5‐triazin‐4(8H)‐one: Synthesis and Conformation of a 5‐Aza‐7‐deazaguanine Fluoronucleoside
Authors: Glaçon Virginie , Seela Frank 
Published: May 2004

AbstractNucleobase‐anion glycosylation of 2‐[(2‐methyl‐1‐oxopropyl)amino]imidazo[1,2‐a]‐1,3,5‐triazin‐4(8H)‐one (6) with 3,5‐di‐O‐benzoyl‐2‐deoxy‐2‐fluoro‐α‐D‐arabinofuranosyl bromide (8) furnishes a mixture of the benzoyl‐protected anomeric 2‐amino‐8‐(2‐deoxy‐2‐fluoro‐D‐arabinofuranosyl)imidazo[1,2‐a]‐1,3,5‐triazin‐4(8H)‐ones 9/10 in a ratio of ca. 1 : 1. After deprotection, the inseparable anomeric mixture 3/4 was silylated. The obtained 5‐O‐[(1,1‐dimethylethyl)diphenylsilyl] derivatives 11 and 12 were separated and desilylated affording the nucleoside 3 and its α‐D anomer 4. Similar to 2′‐deoxy‐2′‐fluoroarabinoguanosine, the conformation of the sugar moiety is shifted from S towards N by the fluoro substituent in arabino configuration.
Confirmation of the Structures of Lutein and Zeaxanthin
Authors: Linden Anthony , Bürgi Bruno , Eugster Conrad Hans 
Published: May 2004

AbstractA series of new esters of lutein (1a) have been prepared with the aim of confirming the structure of lutein via an X‐ray crystal‐structure analysis. Although well crystallized, only one of the derivatives, the (−)‐(1R)‐menthyl carbonate (1i) proved to be useful for a complete structure analysis. The same derivative of zeaxanthin (2a) also allowed its crystal structure to be determined. Both analyses represent the first successful X‐ray crystal structure analyses of the most important xanthophylls. At the same time, they confirm both the constitution and absolute configuration of 1a and 2a that had been deduced earlier by classical methods.
Neoclerodane Diterpenes from Amoora stellato‐squamosa
Authors: Yang Shu‐Min , Wu Shao‐Hua , Qin Xiang‐Dong , Luo Xiao‐Dong , Wu Da‐Gang 
Published: May 2004

AbstractFrom the twigs of Amoora stellato‐squamosa, five new neoclerodane diterpenes have been isolated and characterized, methyl (13E)‐2‐oxoneocleroda‐3,13‐dien‐15‐oate (=methyl (2E)‐3‐methyl‐5‐[(1S,2R,4aR,8aR)‐1,2,3,4,4a,7,8,8a‐octahydro‐1,2,4a,5‐tetramethyl‐7‐oxo‐naphthalen‐1‐yl]pent‐2‐enoate; 1), (13E)‐2‐oxoneocleroda‐3,13‐dien‐15‐ol (=(4aR,7R,8S,8aR)‐1,2,4a,5,6,7,8,8a‐octahydro‐8‐[(E)‐5‐hydroxy‐3‐methylpent‐3‐enyl]‐4,4a,7,8‐tetramethylnaphthalen‐2(1H)‐one; 2), (3α,4β,13E)‐neoclerod‐13‐ene‐3,4,15‐triol (=(1R,2R,4aR, 5S,6R,8aR)‐decahydro‐5‐[(E)‐5‐hydroxy‐3‐methylpent‐3‐enyl]‐1,5,6,8a‐tetramethylnaphthalene‐1,2‐diol; 3), (3α,4β,13E)‐4‐ethoxyneoclerod‐13‐ene‐3,15‐diol (=(1R,2R,4aR,5S,6R,8aR)‐1‐ethoxydecahydro‐5‐[(E)‐5‐hydroxy‐3‐methylpent‐3‐enyl]‐1,5,6,8a‐tetramethylnaphthalen‐2‐ol; 4), and (3α,4β,14RS)‐neoclerod‐13(16)‐ ene‐3,4,14,15‐tetrol (=(1R,2R,4aR,5S,6R,8aR)‐decahydro‐5‐[3‐(1,2‐dihydroxyethyl)but‐3‐enyl]‐1,5,6,8a‐tetramethylnaphthalene‐1,2‐diol; 5), together with two known compounds, (13E)‐neocleroda‐3,13‐diene‐15,18‐diol (6) and (13S)‐2‐oxoneocleroda‐3,14‐dien‐13‐ol (7).
Novel cell patterning using microheater‐controlled thermoresponsive plasma films
Authors: Cheng Xuanhong , Wang Yanbing , Hanein Yael , Böhringer Karl F. , Ratner Buddy D. 
Published: May 2004

AbstractA novel approach is reported for cell patterning based on addressable microheaters and a poly(N‐isopropyl acrylamide) (pNIPAM) themoresponsive coating. This thermoresponsive coating is created by a radio frequency NIPAM plasma and is denoted as plasma polymerized NIPAM (ppNIPAM). Films of ppNIPAM with a good retention of monomer side‐chain functionality are produced using low‐power continuous plasma deposition. Cell adhesion and cell detachment tests indicate that the surface switches between adhesive and nonadhesive behaviors as a function of temperature. The use of a photolithographically fabricated microheater array allows the ppNIPAM transition to occur spatially under the control of individual heaters. This localized change in the surface adhesive behavior is used to direct site‐specific cell attachment. Patterned adhesion of two types of cells has been visualized on the array through fluorescent markers. Applications for diagnostic devices, cell‐based sensors, tissue engineering, and cell transfection are envisioned. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 70A: 159–168, 2004
p47phox PX domain of NADPH oxidase targets cell membrane via moesin‐mediated association with the actin cytoskeleton
Authors: Zhan Yong , He Dandan , Newburger Peter E. , Zhou G. Wayne 
Published: May 2004

AbstractActivation of phagocytic NADPH oxidase requires association of its cytosolic subunits with the membrane‐bound flavocytochrome. Extensive phosphorylation of the p47phox subunit of NADPH oxidase marks the initiation of this activation process. The p47phox subunit then translocates to the plasma membrane, bringing the p67phox subunit to cytochrome b558 to form the active NADPH oxidase complex. However, the detailed mechanism for targeting the p47phox subunit to the cell membrane during activation still remains unclear. Here, we show that the p47phox PX domain is responsible for translocating the p47phox subunit to the plasma membrane for subsequent activation of NADPH oxidase. We also demonstrate that translocation of the p47phox PX domain to the plasma membrane is not due to interactions with phospholipids but rather to association with the actin cytoskeleton. This association is mediated by direct interaction between the p47phox PX domain and moesin. © 2004 Wiley‐Liss, Inc.
Nanoporous aluminum oxide affects neutrophil behaviour
Authors: Karlsson M. , Johansson A. , Tang L. , Boman M. 
Published: May 2004

AbstractThis study evaluates neutrophil responses on aluminum oxide membranes. Using an in vitro cell culture system, we have found that the pore size (20 and 200 nm in diameter) of alumina membranes have a significant effect on leukocyte morphology and activation. Specifically, our results show that 20‐nm pore‐size membranes were more potent in triggering PMN spreading and extending of pseudopodia than 200‐nm pore‐size membranes. The morphological changes are also associated with cell activation. In fact, adherent neutrophils on 20‐nm pore‐size membranes elicit much stronger initial oxygen free radical production. Overall, our results point out that membrane pore size significantly affects the extent of cellular responses of adherent neutrophils. Microsc. Res. Tech. 63:259–265, 2004. © 2004 Wiley‐Liss, Inc.
Intraoperative imprint cytology of sentinel nodes in breast cancer
Authors: Barranger Emmanuel , Antoine Martine , Grahek Dany , Callard Patrice , Uzan Serge 
Published: May 2004

AbstractBackground and ObjectivesSentinel node (SN) biopsy is a new standard of care for axillary node staging in patients with early‐stage, clinically node‐negative breast cancer. A second operation can be avoided when the results are available intraoperatively. However, there is no standard intraoperative method for SN assessment. The aim of this study was to evaluate intraoperative imprint cytology (IC) for the detection of SN involvement in patients with early‐stage breast cancer.MethodsOne hundred eighty‐five consecutive patients with a breast tumor underwent SN biopsy with intraoperative IC. The SN was bisected and a touch preparation was made with a glass slide, on both sides of the cut. Permanent sections were evaluated with H&E and immunohistochemical staining. The IC results were compared with the final histologic results.ResultsThe sensitivity, specificity, accuracy, and positive and negative predictive values of IC were 33.3, 78.4, 78.9, 90, and 77.5%, respectively. IC was more sensitive for macrometastases than for micrometastases. In the 118 patients studied after the learning phase, 9 patients with a positive SN by IC avoided a second operation.ConclusionsIntraoperative IC of SNs appears to be reasonably reliable in patients with breast cancer, permitting axillary dissection during the same surgical procedure when positive. In contrast, sensitivity for detection of micrometastases is low. J. Surg. Oncol. 2004;86:128–133. © 2004 Wiley‐Liss, Inc.
Comparison of repeatability of non‐invasive and invasive urodynamics
Authors: Mastrigt R. van , Huang Foen Chung J.W.N.C. 
Published: May 2004

AbstractAimsWe have developed a method for the non‐invasive measurement of urinary bladder pressure, and we apply this method in a longitudinal study of changes in bladder contractility in response to prostatic enlargement. In each volunteer in this study, we measure the bladder pressure twice. In the present study we have used this data to compare the repeatability of the non‐invasive method to that of pressure‐flow studies in a comparable population of patients.MethodsDifference plots were made of non‐invasive bladder pressure measurements in 457 volunteers and of pressure‐flow studies in a comparable population of 397 male patients. To compare the repeatability of two different methods for clinical measurement, the standard deviation of differences between repeated measurements in one individual needs to be normalised. Often a normalisation by dividing by the mean is done. We show that that normalisation may lead to erroneous results. We have normalised the standard deviations by dividing by the difference between the 97.5th and 2.5th percentile of the mean of the two observations in each subject.ResultsNormalised repeatability of the non‐invasive method was 0.15, that of the various parameters derived from the pressure‐flow studies varied from 0.11 to 0.22.ConclusionsWe conclude that the repeatability of the tested non‐invasive urodynamic method is comparable to, or slightly better than, that of pressure‐flow studies. We further conclude that normalising standard deviations of differences by dividing by the difference between the 97.5th and 2.5th percentile of the mean is a suitable method to compare the repeatability of different methods for clinical measurement. © 2004 Wiley‐Liss, Inc.