bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photochemical Synthesis of Pentacene and its Derivatives
Authors: Yamada Hiroko , Yamashita Yuko , Kikuchi Makoto , Watanabe Hikaru , Okujima Tetsuo , Uno Hidemitsu , Ogawa Takuji , Ohara Keishi , Ono Noboru 
Published: August 2005

AbstractA novel α‐diketone precursor of pentacene, 6,13‐dihydro‐6,13‐ethanopentacene‐15,16‐dione, was prepared and converted successfully to pentacene in 74 % yield by photolysis of the precursor in toluene: Irradiation of the diketone solution in toluene with light of 460 nm under an Ar atmosphere caused the solution to change from yellow to fluorescent orange‐pink within a few minutes, after which, purple precipitates appeared. After 35 min, the solution changed to colorless and the purple precipitates were filtered to give pentacene in 74 % yield. By contrast, in the presence of oxygen, the color of the solution changed from yellow to pale yellow, and only 6,13‐endoperoxide of pentacene was quantitatively obtained. The rate of the reaction upon photolysis was measured by observing the decay of n–π* absorption of the precursor at 460 nm, and was found to be similar in both the presence and absence of oxygen. Therefore, the photoreaction of the α‐diketone precursor seemed to occur via the singlet excited state. Because the T–T absorption of pentacene was observed upon photolysis of the precursor in the nanosecond transient absorption measurement under an Ar atmosphere, the excited triplet state of the pentacene generated singlet oxygen by sensitization, and it reacted with the ground‐state pentacene to give the 6,13‐endoperoxide. The α‐diketone deposited on glass was also converted successfully to pentacene film by photoirradiation. In addition, diketone precursors of a mixture of 2,8‐ and 2,9‐dibromopentacene and 2,6‐trianthrylene were also prepared and their photoconversion was performed.
Highly Enantioselective Phase‐Transfer‐Catalyzed Alkylation of Protected α‐Amino Acid Amides Toward Practical Asymmetric Synthesis of Vicinal Diamines, α‐Amino Ketones, and α‐Amino Alcohols.
Authors: Ooi Takashi , Takeuchi Mifune , Kato Daisuke , Uematsu Yukitaka , Tayama Eiji , Sakai Daiki , Maruoka Keiji 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Highly Chemoselective Reduction of Aromatic Nitro Compounds to the Corresponding Hydroxylamines Catalyzed by Plant Cells from a Grape (Vitis vinifera L.).
Authors: Li Feng , Cui Jingnan , Qian Xuhong , Zhang Rong , Xiao Yi 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Intraabdominal desmoplastic small round cell tumors
Authors: Hassan Imran , Shyyan Roman , Donohue John H. , Edmonson John H. , Gunderson Leonard L. , Moir Christopher R. , Arndt Carola A.S. , Nascimento Antonio G. , Que Florencia G. 
Published: August 2005

AbstractBACKGROUNDIntraabdominal desmoplastic small round cell tumors (IDSRCT) are uncommon but aggressive tumors that occur in young males. To the authors' knowledge, only limited data are available on the natural history and optimal treatment of this disease.METHODSThe authors reviewed 12 patients with IDSRCT who were treated at their institution between January 1991 and December 2001.RESULTSAll patients were males, with a median age of 26 years. All patients were symptomatic at the time of presentation, with a mean duration of symptoms of 2 months. Common presenting symptoms and signs were abdominal pain (67% of patients), palpable abdominal mass (58% of patients), abdominal distension (42% of patients), and hepatomegaly (33% of patients). Six patients (50%) had distant metastases at presentation. Five patients underwent biopsy only. Surgical resection was attempted in seven patients and included macroscopic total resection in three patients and debulking in four patients. All of those patients subsequently developed recurrent or progressive disease, which required a second operation in six patients. Overall, 6 patients (50%) developed symptomatic intestinal obstruction requiring surgical management, and 3 patients (25%) developed ureteral obstruction. All 12 patients received multiagent chemotherapy. Seven patients (55%) also received radiation therapy. The median survival of patients who underwent surgical resection was 34 months, whereas the median survival of patients who underwent biopsy alone was 14 months. One patient remained alive 72 months after he underwent complete resection of primary and recurrent tumors, and 1 patient remained alive with disease 32 months after he underwent complete resection of a primary tumor.CONCLUSIONSPatients with IDSRCT presented with a short duration of nonspecific symptoms, and the disease was fatal almost uniformly, regardless of the treatment modality used. Surgical resection may prolong survival in some patients. Cancer 2005. © 2005 American Cancer Society.
Cytological features of lipoblastoma: A report of three cases
Authors: Kloboves‐Prevodnik V. Veronika , Us‐Krašovec Marija , Gale N. , Lamovec Janez 
Published: August 2005

AbstractLipoblastoma is a rare benign neoplasm occurring mostly in children under the age of three. Accurate preoperative diagnosis is mandatory for planning the treatment. The main aim of this study is to establish the cytological features of lipoblastoma and to answer the question: “Is cytological diagnosis of lipoblastoma reliable?”Preoperative fine‐needle aspiration biopsy (FNAB) and tissue sections of three children treated for lipoblastoma at the Division of Pediatrics, University Medical Center, Ljubljana, Slovenia, in the period from 1997 to 2004 were reexamined. The Giemsa‐ and Papanicolaou‐stained FNAB smears were moderately or poorly cellular and contained lipocytes, lipoblasts, and spindle cells in various proportions. The tumor cells were in clusters and tissue fragments or as single cells. Thin branching capillaries were observed in most of the clusters and tissue fragments. In the background, abundant myxoid extracellular material and naked oval nuclei were present.In the first case, the cytological diagnosis was benign soft‐tissue tumor, in the second the diagnosis was not conclusive and the last case was correctly diagnosed as lipoblastoma. In the differential diagnosis of the second case, both lipoblastoma and liposarcoma were considered cytologically as well as histologically. At 7‐yr follow‐up, there is no evidence of the disease.Thus, we conclude that lipoblastoma with typical cytological features could be accurately diagnosed by FNAB. However, tumors containing numerous lipoblasts could pose a diagnostic problem. Diagn. Cytopathol. 2005;33:195–200. © 2005 Wiley‐Liss, Inc.
Osteosarcoma metastatic to adrenal gland diagnosed by fine‐needle aspiration
Authors: Siddiqui Noman H. , Jani Jigna 
Published: August 2005

AbstractOsteosarcoma, a primary malignant tumor of the long bones, frequently metastasizes to the lungs. We report an unusual case of osteosarcoma metastatic to the right adrenal gland in a 37‐yr‐old male who presented 8 yr after remission with an adrenal mass. A preoperative diagnosis was made by fine‐needle aspiration (FNA) biopsy. FNA biopsy revealed pleomorphic oval cells with prominent nucleoli, spindle cells, and giant tumor cells. Diagnostic osteoid was readily seen on smears and was also detected by polarization of cell‐block section. Immunocytochemical stains revealed positivity of tumor cells for vimentin and osteonectin. Cytokeratin stains were negative. The cytologic diagnosis of metastatic Osteosarcoma was made, which was later confirmed upon resection of tumor by histology. Although the role of FNA in the diagnosis of primary bone tumors, including osteogenic sarcoma (OGS), remains controversial, this case, however, demonstrates the value of FNA biopsy combined with immunocytochemistry performed on the aspirated material in diagnosing osteosarcoma from an unusual location such as the adrenal gland. Diagn. Cytopathol. 2005;33:201–204. © 2005 Wiley‐Liss, Inc.
Preservation of β‐cell function during immune‐mediated, B7‐1‐dependent α‐cell destruction
Authors: Skak Kresten , Haase Claus , Michelsen Birgitte K. 
Published: August 2005

AbstractType 1 diabetes (T1D) is an autoimmune disease in which the pancreatic β‐cells are destroyed in an immune‐mediated process. In one mouse model of T1D, the co‐expression of the costimulatory molecule, B7–1, and the pro‐inflammatory cytokine, tumor necrosis factor (TNF)‐α, on the β‐cells leads to massive insulitis and loss of β‐cells, resulting in T1D. Here, we have investigated whether the specific loss of β‐cells is due to an intrinsic defect in the β‐cells or is a direct consequence of B7–1 expression. We show that transgenic mice expressing TNF‐α on the β‐cells and B7–1 on the α‐cells are resistant to the development of diabetes despite B7‐1‐dependent loss of α‐cells and a massive islet inflammation consisting of T cells, B cells, macrophages and dendritic cells. Furthermore, islets with α‐cell expression of B7–1 develop α‐cell destruction and heavy infiltration, but maintain functional β‐cells when they are engrafted into diabetic mice that co‐express TNF‐α and B7–1 on the β‐cells. Thus, our results show that the β‐cells are able to survive in a severely inflamed organ where the neighboring α‐cells are destroyed, suggesting that in this model B7–1 expression on the target cells is the primary determinant for the loss of islet cells.
Human resting CD16–, CD16+ and IL‐2‐, IL‐12‐, IL‐15‐ or IFN‐α‐activated natural killer cells differentially respond to sphingosylphosphorylcholine, lysophosphatidylcholine and platelet‐activating factor
Authors: Jin Yixin , Damaj Bassam B. , Maghazachi Azzam A. 
Published: August 2005

AbstractThe phosphorylcholine‐containing lipid lysophosphatidylcholine (LPC) is abundant in the bloodstream, whereas sphingosylphosphorylcholine (SPC) and platelet‐activating factor (PAF) highly accumulate at inflamed sites. Utilizing RT‐PCR, flow cytometry and immunoblot analyses, we show for the first time that ovarian cancer G protein‐coupled receptor 1, the receptor for SPC, is expressed in IL‐2‐, IL‐12‐ and IL‐15‐activated but not in resting CD16–, resting CD16+ or IFN‐α‐activated NK cells. Similarly, G2 accumulation and PAF receptor are variably expressed in these subsets of NK cells. SPC, LPC and PAF differentially induce the chemotaxis of resting and activated NK cells. In the chemotaxis assay, it is observed that resting CD16–CD56bright and CD16+CD56dim cells predominantly respond to LPC, whereas activated NK cells, regardless of the sort of stimulus, robustly respond to PAF. SPC is also a potent chemoattractant for IL‐2‐, IL‐12‐ and IL‐15‐ but not for IFN‐α‐activated NK cells. Further analysis shows that, depending on the cytokine pattern of NK cell activation, phosphorylcholine‐containing lipids differentially affect IFN‐γ secretion by these cells. Our results provide one possible explanation for the tissue compartmentation of NK cells and their ability to secrete IFN‐γ. Furthermore, these results may provide novel information regarding NK cell regulation during inflammation.
Lewis Acid Induced [2+2] Cycloadditions of Silyl Enol Ethers with α,β‐Unsaturated Esters: A DFT Analysis
Authors: Arnó Manuel , Zaragozá Ramón J. , Domingo Luis R. 
Published: August 2005

AbstractThe Lewis acid (LA) induced cycloaddition of trimethysilyl vinyl ether with methyl acrylate has been studied by DFT methods at the B3LYP/6‐31G* level. In the absence of an LA, a [4+2] cycloaddition between the silyl enol ether and methyl acrylate in the s‐cis conformation takes place through an asynchronous, concerted bond‐formation process. This cycloaddition presents a large activation enthalpy of 21.1 kcal mol–1. Coordination of the LA AlCl3 to the carbonyl oxygen atom of methyl acrylate yields a change of molecular mechanism from a concerted to a two‐step mechanism and produces a drastic reduction of the activation energy. This stepwise mechanism is initialized by the nucleophilic attack of the enol ether at the β‐position of methyl acrylate in a Michael‐type addition. The very low activation energy (7.1 kcal mol–1)associated with this nucleophilic attack can be related to the increase of the electrophilicity of the LA‐coordinated α,β‐unsaturated ester, which favors the cycloaddition through a polar process. The subsequent ring‐closure allows the formation of the corresponding [2+2] and [4+2] cycloadducts. While the [4+2] cycloadduct is formed by kinetic control, the [2+2] cycloadducts are formed by thermodynamic control. The energetic results provide an explanation for the conversion of [4+2] cycloadducts into the thermodynamically more stable [2+2] ones. The cis/trans ratio found for the catalytic [2+2] process is in agreement with the experimental outcome. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Synthesis, Characterisation and Nonlinear Optical Properties of Two‐Dimensional Octupolar Systems Based on Phthalocyanine Compounds
Authors: Quintiliani Maurizio , García‐Frutos Eva M. , Gouloumis Andreas , Vázquez Purificación , Ledoux‐Rak Isabelle , Zyss Joseph , Claessens Christian G. , Torres Tomás 
Published: August 2005

AbstractFour phthalocyanine‐based compounds with pseudo D3h symmetry have been synthesised and fully characterised. Palladium cross‐coupling methodologies were employed in order to synthesise 1,3,5‐tris[(phthalocyaninyl)ethenyl]benzene (Heck) and 1,3,5‐tris[(phthalocyaninyl)ethynyl]benzene (Sonogashira) derivatives. Knoevenagel condensation conditions were then applied to the synthesis of 1,3,5‐tris[cyano(phthalocyaninyl)ethenyl]benzene and 2,4,6‐tris[(phthalocyaninyl)ethenyl]‐1,3,5‐triazine. Preliminary second‐order nonlinear optical studies, by hyper‐Rayleigh scattering measurements, revealed that the compounds containing ethenyl linkers induce a strong octupolar effect while the ethynyl‐containing compound does not show any octupolar enhancement. The introduction of a triazine central core does not modify significantly the nonlinear optical behaviour of the compound. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Explicit algebraic stress modelling of homogeneous and inhomogeneous flows
Authors: Chiu T. H. , Yeh L. K. , Lin C. A. , Chern S. J. 
Published: August 2005

AbstractCapability of the explicit algebraic stress models to predict homogeneous and inhomogeneous shear flows are examined. The importance of the explicit solution of the production to dissipation ratio is first highlighted by examining the algebraic stress models performance at purely irrotational strain conditions. Turbulent recirculating flows within sudden expanding pipes are further simulated with explicit algebraic stress model and anisotropic eddy viscosity model. Both models predict better stress–strain interactions, showing reasonable shear layer developments. The anisotropic stress field are also accurately predicted by the models, though the anisotropic eddy viscosity model of Craft et al. returns marginally better results. Copyright © 2005 John Wiley & Sons, Ltd.
An eddy viscosity model with near‐wall modifications
Authors: Rahman M. M. , Siikonen T. 
Published: August 2005

AbstractAn extended version of the isotropic k–ε model is proposed that accounts for the distinct effects of low‐Reynolds number (LRN) and wall proximity. It incorporates a near‐wall correction term to amplify the level of dissipation in nonequilibrium flow regions, thus reducing the kinetic energy and length scale magnitudes to improve prediction of adverse pressure gradient flows, involving flow separation and reattachment. The eddy viscosity formulation maintains the positivity of normal Reynolds stresses and the Schwarz' inequality for turbulent shear stresses. The model coefficients/functions preserve the anisotropic characteristics of turbulence. The model is validated against a few flow cases, yielding predictions in good agreement with the direct numerical simulation (DNS) and experimental data. Comparisons indicate that the present model is a significant improvement over the standard eddy viscosity formulation. Copyright © 2005 John Wiley & Sons, Ltd.
Analysis of chromosome breakpoints in neuroblastoma at sub‐kilobase resolution using fine‐tiling oligonucleotide array CGH
Authors: Selzer Rebecca R. , Richmond Todd A. , Pofahl Nathan J. , Green Roland D. , Eis Peggy S. , Nair Prakash , Brothman Arthur R. , Stallings Raymond L. 
Published: August 2005

AbstractUnderstanding the genes and genetic pathways targeted by recurrent chromosomal imbalances in malignancy, along with the molecular mechanisms that generate the imbalances, are important problems in cancer biology. In this report, we demonstrate that oligonucleotide array CGH (oaCGH) analysis can routinely map chromosomal imbalance breakpoints at exon‐level resolution, including imbalances that are single copy number genomic alterations. Different tiling‐path array designs were used in this study: a whole‐genome array with a 6‐kb median probe spacing and fine‐tiling arrays for selected genomic regions with either 50‐ or 140‐bp median probe spacing. In both array formats, oligonucleotide probes were of isothermal design and were tiled through genic and inter‐genic regions. Whole‐genome oaCGH analysis of two neuroblastoma cell lines and three primary tumors led to the identification of 58 chromosomal breakpoints that generated 45 large‐scale partial chromosomal imbalances (>2 Mb). An unexpectedly high proportion (34%) of these breakpoint intervals mapped to regions containing segmental duplications. In addition, 88 smaller‐sized regions (<2 Mb) of imbalance were detected, the majority of which mapped to segmentally duplicated regions and may reflect constitutional copy number polymorphisms. The chromosomal breakpoints for 12 recurrent abnormalities exhibited in neuroblastoma tumors and cell lines, including MYCN amplicon boundaries, loss of 3p, loss of 11q, and gain of 17q, could be mapped to intervals ranging from 50 bp to 10 kb in size using high‐density fine‐tiling oligonucleotide microarrays. Fine‐tiling oaCGH analysis provides an unprecedented level of resolution, allowing detailed mapping of recurrent unbalanced chromosomal abnormalities. Supplementary material for this article can be found on the Genes, Chromosomes, and Cancer website at http://www.interscience.wiley.com/jpages/1045‐2257/suppmat/index.html. © 2005 Wiley‐Liss, Inc.
Expression of Nav1.6 sodium channels by Schwann cells at neuromuscular junctions: Role in the motor endplate disease phenotype
Authors: Musarella Magali , Alcaraz Gisèle , Caillol Ghislaine , Boudier Jean‐Louis , Couraud François , Autillo‐Touati Amapola 
Published: August 2005

AbstractIn addition to their role in action potential generation and fast synaptic transmission in neurons, voltage‐dependent sodium channels can also be active in glia. Terminal Schwann cells (TSCs) wrap around the nerve terminal arborization at the neuromuscular junction, which they contribute to shape during development and in the postdenervation processes. Using fluorescent in situ hybridization (FISH), immunofluorescence, and confocal microscopy, we detected the neuronal Nav1.6 sodium channel transcripts and proteins in TSCs in normal adult rats and mice. Nav1.6 protein co‐localized with the Schwann cell marker S‐100 but was not detected in the SV2‐positive nerve terminals. The med phenotype in mice is due to a mutation in the SCN8A gene resulting in loss of Nav1.6 expression. It leads to early onset in postnatal life of defects in neuromuscular transmission with minimal alteration of axonal conduction. Strikingly, in mutant mice, the nonmyelinated pre‐terminal region of axons showed abundant sprouting at neuromuscular junctions, and most of the α‐bungarotoxin‐labeled endplates were devoid of S‐100‐ or GFAP‐positive TSCs. Using specific antibodies against the Nav1.2 and Nav1.6 sodium channels, ankyrin G and Caspr 1, and a pan sodium channel antibody, we found that a similar proportion of ankyrin G‐positive nodes of Ranvier express sodium channels in mutant and wild‐type animals and that nodal expression of Nav1.2 persists in med mice. Our data supports the hypothesis that the lack of expression of Nav1.6 in Schwann cells at neuromuscular junctions might play a role in the med phenotype. © 2005 Wiley‐Liss, Inc. © 2005 Wiley‐Liss, Inc.
Efficient methods of discharge measurements in rivers and streams based on the probability concept
Authors: Chiu Chao‐Lin , Hsu Shih‐Meng , Tung Ning‐Chien 
Published: August 2005

AbstractRegularities exist in fluid flows and can be represented by a set of constants. These constants are functions of the parameter of a probability distribution that exhibits resilience and stability under various flow conditions. Together, these regularities form a network and interact with each other, such that if one is known then the others can be determined from it. The regularities and their network explain the various fluid‐flow phenomena and can be used in analysis of rivers and streams. For example, they can be used as the basis to develop simple and efficient methods of discharge measurements as presented herein, which only require velocity sampling at a single point on a water surface or a few points on a single vertical. Because of their simplicity and the short time requirement, these methods can be easily automated for collecting discharge data in unsteady, high flows that are badly needed for real‐time flow forecasting and design of flood control structures, and for advancing the fundamental, scientific knowledge in hydrology. Copyright © 2005 John Wiley & Sons, Ltd.
Effects of channel regulation on salt intrusion and residual circulation of Keelung River
Authors: Liu Wen‐Cheng 
Published: August 2005

AbstractA vertical (laterally integrated) two‐dimensional numerical model was applied to study the hydrodynamic characteristics, salt‐water intrusion and residual circulation in the Danshuei River estuarine system. The cross‐sectional profiles measured in 2001 and 1990 respectively represent the conditions after and before channel regulation in the Keelung River. The model was re‐verified with the available hydrological data measured in 2001. Detailed model re‐verification has been conducted with water surface elevations, tidal current, and salinity distributions measured. The overall performance of the model is in qualitative agreement with the available field data. The model was then used to investigate the change in tidal ranges, salt‐water intrusion, and residual circulation as a result of channel regulation in the Keelung River. The model simulations indicate that more tidal energy propagates into the estuarine system before channel regulation because of the substantial increase in river cross‐sections. The residual circulations before channel regulation are greater than those after channel regulation and result in the limits of the salt intrusion before channel regulation being extended farther inland than those after channel regulation. This may show that channel regulation for flood control in the Keelung River did not contribute to the expansion of the mangrove areas and the disappearance of freshwater marshes at the Kuan‐Du wetlands. Copyright © 2005 John Wiley & Sons, Ltd.